How do we correctly translate Matthew 24:34 (emphasis added)?

Matthew 24:34 (KJV)
    Verily I say unto you, This generation shall not pass, till all these things be fulfilled.

The interpretation of the above Passage is EXTREMELY important to the Preterist who unwisely suggest that ALL of the events of Jesus’ prophetic Olivet Discourse are now ‘fulfilled’ and past. 

However, this may NOT necessarily be the case because they are basing their assumption on a questionable and debatable translation of the greek word ‘ginomai’ translated as ‘fulfilled’ in the above related Passage.  Per definition the greek word gignomai is a very flexible verb and can be as neutral as a synonym for the verb "to be", or as specific as a synonym for the verb "to be born".  Thus, this colorful verb can potentially mean many things. 

ginomai, Greek 1096, Strong’s

ginomai, ghin'-om-ahee; a prolonged and middle form of a primary verb; to cause to be (“gen”-erate), i.e. (reflexive) to become (come into being), used with great latitude (literal, figurative, intensive, etc.) :- arise, be assembled, be (-come, -fall, -have self), be brought (to pass), (be) come (to pass), continue, be divided, draw, be ended, fall, be finished, follow, be found, be fulfilled, + God forbid, grow, happen, have, be kept, be made, be married, be ordained to be, partake, pass, be performed, be published, require, seem, be showed, × soon as it was, sound, be taken, be turned, use, wax, will, would, be wrought. 

Therefore, in the context of a continuing series of events ("event" being the key), Matthew is anticipating that we the reader will easily realize that gignomai here means the "happening / becoming / coming to pass" of those events. 

Thus, what one can reasonably suggest is that Jesus was prophetically revealing in Matt. 24 that the prophetic events He had described would ALREADY be in progress - happening/becoming/coming to pass  - even before the generation in question (the one of that day) would come to an end. 

Going forward, posted below is Matt. 24:34 from the respected Interlinear Scripture Analyzer (ISA) and as you can see Strong’s 1096 greek ‘ginomai’ is a – Verb, 2^nd Aorist, Middle Voice, Deponent, Subjunctive Mood, 3^rd Person Singular.  The verb ‘ginomai’ is translated as ‘may be becoming’ with respect to the greek subjunctive mood (may).  

https://biblehub.com/interlinear/matthew/24-34.htm

281 [e] 34   amēn 34   ἀμὴν 34   Truly 34   Heb 3004 [e] legō λέγω I say V-PIA-1S 4771 [e] hymin ὑμῖν to you PPro-D2P 3754 [e] hoti ὅτι that Conj 3756 [e] ou οὐ no Adv 3361 [e] mē μὴ not Adv 3928 [e] parelthē παρέλθῃ will have passed away V-ASA-3S 3588 [e] hē ἡ the Art-NFS 1074 [e] genea γενεὰ generation N-NFS 3778 [e] hautē αὕτη this DPro-NFS 2193 [e] heōs ἕως until Conj 302 [e] an ἂν  -  Prtcl 3956 [e] panta πάντα all Adj-NNP 3778 [e] tauta ταῦτα these things DPro-NNP 1096 [e] genētai γένηται  . shall have taken place V-ASM-3S

Hence, the greek subjunctive is the mood of “probability and possibility,” and its occurrence is conditional upon a person’s free will to make it happen.  The aorist subjunctive can be defined as an event that will punctuate the succession of history if an individual is faithful to accomplish it as an act of their free will. 

To reiterate Matt. 24:34 is declaring that the events of the Olivet Discourse would already be 'occurring' even before the generation of the day of Jesus passed away (emphasis added). 

“Thus, what one can reasonably suggest is that Jesus was prophetically revealing in Matt. 24 that the prophetic events He had described would ALREADY be in progress - happening/becoming/coming to pass  - even before the generation in question (the one of that day) would come to an end.” 

Meanwhile, the Preterists suggest that the greek word ‘ginomai’ CANNOT be accurately grammatically translated with respect to Matt. 24:34, Mk 13:30, and Lk. 21:32 as happening/becoming/coming to pass.   

Going forward, here is a list of Scriptures in the KJV that uses this same EXACT greek word ‘ginomai’ and its same EXACT grammatical tense (v 2^nd Aor midD Sub 3^rd Sg) as used in Matt. 24:34 Mk 13:30, and Lk. 21:32.  Do you see any of the 41 referenced Passages translated as ‘fulfilled’ – try plugging fulfilled into these following Passages. 

Matt. 10:25, 18:12-13, 21:19, 23:15, 23:26, 24:20-21, 24:32, 26:5, Mk. 9:50, 13:18-19, 28, Lk. 1-20, 4:3, 14:12, 20:14, 23:31, Jn. 5:14, 9:22, 13:19, 14:29, Acts 20:16, Romans 3:19, 7:3, 7:13, 15:16, 1Cor. 3:18, 8:9, 9:15, 16:10, 2Cor. 8:14, Gal. 3:14, Eph. 6:3, Col. 1:18, 1Thes. 3:5, 2Thes. 2:7, Phil. 1:6, Heb. 2:17. 

Matthew 10:25
    It is enough for the disciple that he be as his master, and the servant as his lord. If they have called the master of the house Beelzebub, how much more shall they call them of his household?  

Matthew 18:12-13
    How think ye? if [there be] a man have an hundred sheep, and one of them be gone astray, doth he not leave the ninety and nine, and goeth into the mountains, and seeketh that which is gone astray? [13] And if so be that he find it, verily I say unto you, he rejoiceth more of that sheep, than of the ninety and nine which went not astray.  

Matthew 21:19
    And when he saw a fig tree in the way, he came to it, and found nothing thereon, but leaves only, and said unto it, Let no fruit grow on thee henceforward for ever. And presently the fig tree withered away.  

Matthew 23:15
    Woe unto you, scribes and Pharisees, hypocrites! for ye compass sea and land to make one proselyte, and when he is made, ye make him twofold more the child of hell than yourselves.  

Matthew 23:26
    Thou blind Pharisee, cleanse first that which is within the cup and platter, that the outside of them may be clean also.  

Matthew 24:20-21
    But pray ye that your flight be not in the winter, neither on the sabbath day: [21] For then shall be great tribulation, such as was not since the beginning of the world to this time, no, nor ever shall be.

Matthew 24:32
    Now learn a parable of the fig tree; When his branch is yet tender, and putteth forth leaves, ye know that summer is nigh:  

Matthew 26:5
    But they said, Not on the feast day, lest there be an uproar among the people.

 Mark 9:50
    Salt is good: but if the salt have lost his saltness, wherewith will ye season it? Have salt in yourselves, and have peace one with another.  

Mark 13:18-19
    And pray ye that your flight be not in the winter. [19] For in those days shall be affliction, such as was not from the beginning of the creation which God created unto this time, neither shall be.  

Mark 13:28
    Now learn a parable of the fig tree; When her branch is yet tender, and putteth forth leaves, ye know that summer is near:  

Luke 1:20
    And, behold, thou shalt be dumb, and not able to speak, until the day that these things shall be performed, because thou believest not my words, which shall be fulfilled in their season.

 Luke 4:3
    And the devil said unto him, If thou be the Son of God, command this stone that it be made bread.  

Luke 14:12
    Then said he also to him that bade him, When thou makest a dinner or a supper, call not thy friends, nor thy brethren, neither thy kinsmen, nor thy rich neighbours; lest they also bid thee again, and a recompence be made thee.  

Luke 20:14
    But when the husbandmen saw him, they reasoned among themselves, saying, This is the heir: come, let us kill him, that the inheritance may be ours.  

Luke 23:31
    For if they do these things in a green tree, what shall be done in the dry?

John 5:14
    Afterward Jesus findeth him in the temple, and said unto him, Behold, thou art made whole: sin no more, lest a worse thing come unto thee.  

John 9:22
    These words spake his parents, because they feared the Jews: for the Jews had agreed already, that if any man did confess that he was Christ, he should be put out of the synagogue.

John 13:19
    Now I tell you before it come, that, when it is come to pass, ye may believe that I am he.

 John 14:29
    And now I have told you before it come to pass, that, when it is come to pass, ye might believe.

Acts 20:16
    For Paul had determined to sail by Ephesus, [so as not happen] because he would not spend the time in Asia: for he hasted, if it were possible for him, to be at Jerusalem the day of Pentecost.  

Romans 3:19
    Now we know that what things soever the law saith, it saith to them who are under the law: that every mouth may be stopped, and all the world may become guilty before God.

 Romans 7:3
    So then if, while her husband liveth, she be married to another man, she shall be called an adulteress: but if her husband be dead, she is free from that law; so that she is no adulteress, though she be married to another man.

Romans 7:13
    Was then that which is good made death unto me? God forbid. But sin, that it might appear sin, working death in me by that which is good; that sin by the commandment might become exceeding sinful. 

Romans 15:16
    That I should be the minister of Jesus Christ to the Gentiles, ministering the gospel of God, that the offering up of the Gentiles might be acceptable, being sanctified by the Holy Ghost.

 1 Cor. 3:18
    Let no man deceive himself. If any man among you seemeth to be wise in this world, let him become a fool, that he may be wise.  

1 Cor. 8:9
    But take heed lest by any means this liberty of yours become a stumblingblock to them that are weak.  

1 Cor. 9:15
    But I have used none of these things: neither have I written these things, that it should be so done unto me: for it were better for me to die, than that any man should make my glorying void.  

1 Cor. 16:10
    Now if Timotheus come, see that he may be with you without fear: for he worketh the work of the Lord, as I also do.  

2 Cor. 8:14
    But by an equality, that now at this time your abundance may be a supply for their want, that their abundance also may be a supply for your want: that there may be equality:

 Galatians 3:14
    That the blessing of Abraham might come on the Gentiles through Jesus Christ; that we might receive the promise of the Spirit through faith.

 Ephes. 6:3
    That it may be well with thee, and thou mayest live long on the earth.

 Col. 1:18
    And he is the head of the body, the church: who is the beginning, the firstborn from the dead; that in all things he might have the preeminence.

 1 Thes. 3:5
    For this cause, when I could no longer forbear, I sent to know your faith, lest by some means the tempter have tempted you, and our labour be in vain.

 2 Thes. 2:7
    For the mystery of iniquity doth already work: only he who now letteth will let, until he be taken out of the way.  

Philemon 1:6
    That the communication of thy faith may become effectual by the acknowledging of every good thing which is in you in Christ Jesus.  

Hebrews 2:17
    Wherefore in all things it behoved him to be made like unto his brethren, that he might be a merciful and faithful high priest in things pertaining to God, to make reconciliation for the sins of the people.  

With respect to the English word 'generation' used in Matthew 24:34, we find that the English word ‘generation’ has undergone a somewhat semantic transformation so that the meaning of the word today is much more narrow than that compared to the Greek word ‘genea’. 

For example, the older Oxford English dictionary relates the following now obsolete (latest attested use 1727) definition of the word ‘generation’ which is defined as a ‘class, kind or set of persons’.  The Strong’s greek meaning of the word ‘genea’ also echoes this same definition – the persons of an age where the timeframe of the ‘age’ is used in a broad and figurative sense – i.e., from the foundation of the world, form Abel to Zacharias, etc. (emphasis added) . 

genea, Greek 1074, Strong’s

genea, ghen-eh-ah'; from (a presumed derivative of) Greek 1085 (genos); a generation; by implication an age (the period or the persons) :- age, generation, nation, time. 

Therefore, a ‘generation’ can reasonably be assumed to be ‘a group of people with a common bond or characteristic; a certain class or type of people’.  This definition is well supported and evidenced in the OT with respect to Proverbs 30:11-14 which details four different types/classifications of people (NOT race nor time but class). 

Proverbs 30:11-14
    There is a generation that curseth their father, and doth not bless their mother. [12] There is a generation that are pure in their own eyes, and yet is not washed from their filthiness. [13] There is a generation, O how lofty are their eyes! and their eyelids are lifted up. [14] There is a generation, whose teeth are as swords, and their jaw teeth as knives, to devour the poor from off the earth, and the needy from among men.  

Moreover, Jesus declared in Lk. 11:50 that the blood of ALL of the prophets slain from the foundation of the world would be required of ‘this generation’.    

Luke 11:50
    That the blood of all the prophets, which was shed from the foundation of the world, may be required of this generation;  

We must ask, how could a narrowly defined generation (the Jews present in Jesus’ day) be accountable for the shedding of ALL of the blood of the prophets from the foundation of the world?  To this end, Jesus declares over and over again that ‘this generation’ in question to be a ‘wicked and adulterous generation’ (class of people) which also included their fathers. 

Luke 11:47-49
   Woe unto you! for ye build the sepulchres of the prophets, and your fathers killed them. [48] Truly ye bear witness that ye allow the deeds of your fathers: for they indeed killed them, and ye build their sepulchres. [49] Therefore also said the wisdom of God, I will send them prophets and apostles, and some of them they shall slay and persecute:

Going forward, here are several NT Scriptural examples of where the greek word ‘genea’ is used to suggest a ‘class of people’. (emphasis added) 

Luke 16:8
    And the lord commended the unjust steward, because he had done wisely: for the children of this world are in their generation wiser than the children of light.  

The important contextual clue to the characteristic of the group of people referred to in the above Passage is the word ‘their’ which qualifies genea. Therefore, the NIV, NEB and JB have translated it as ‘dealing with people of their own kind.’  Thus, the suggestion is ‘people like themselves in their worldliness’. 

Acts 2:40
    And with many other words did he testify and exhort, saying, Save yourselves from this untoward generation.  

Here in Acts 2:40 the contextual clue is a ‘untoward/crooked generation’ – a crooked group of people.  Hence, ‘disassociate yourselves from those wicked people and be saved.’ 

Philip. 2:15
   That ye may be blameless and harmless, the sons of God, without rebuke, in the midst of a crooked and perverse nation [genea], among whom ye shine as lights in the world;  

The contextual clue to the above Passage is the characteristic feature of the group of people referred to as a ‘crooked and perverse’ generation.  The GNB translates Philip. 2:15 as, “in a world of corrupt and sinful people.”   Meanwhile, the NLT has “a dark world full of crooked and perverse people.” 

Matthew 17:17
   Then Jesus answered and said, O faithless and perverse generation, how long shall I be with you? how long shall I suffer you? bring him hither to me.  

Again the characteristic feature of the people referred to in Matt. 17:17 is shown by the qualifiers ‘faithless and perverse’.  The NLT translates it as “You stubborn, faithless people!”   Nonetheless, the actual reference being made by Jesus was to the ‘character/classification’ of His disciples. 

Matthew 12:39 (Mk. 8:12, Matt. 16:4, Lk. 11:29)
    But he answered and said unto them, An evil and adulterous generation seeketh after a sign; and there shall no sign be given to it, but the sign of the prophet Jonas:  

As noted before, the above characteristics of the people referred to are shown by the qualifiers of an ‘evil and spiritually adulterous generation’.

In summary, I suggest that the above body of evidence more than amply supports the translation of Matthew 24:34 as being one of prophetic events in progress even before the passing of the generation of Jesus' day.