43 Heb “For who knows what is good for a man in life?” The rhetorical question (“For who knows …?”) is a negative affirmation, expecting a negative answer: “For no one knows …!” (see E. W. Bullinger, Figures of Speech, ). The translation renders this rhetorical device as a positive affirmation.
44 The vav prefixed to וְיַעֲשֵׂם (véya’asem, conjunction + Qal imperfect 3rd person masculine singular from עָשַׂה, ’asah, “to do” + 3rd person masculine plural suffix) functions in an explanatory or epexegetical sense (“For …”).
45 The 3rd person masculine plural suffix on the verb וְיַעֲשֵׂם (véya’asem, conjunction + Qal imperfect 3rd person masculine singular from ָָעשַׂה, ’asah, “to do” + 3rd person masculine plural suffix) refers to מִסְפַּר יְמֵי־חַיֵּי הֶבְלוֹ (mispar yéme-khayye hevlo, “the few days of his fleeting life”). The suffix may be taken as an objective genitive: “he spends them [i.e., the days of his life] like a shadow” ( I ָָעשַׂה 8) or as a subjective genitive: “they [i.e., the days of his life] pass like a shadow” ( 795 ָָעשַׂה II.11).
46 Heb “Who can tell the man what shall be after him under the sun?” The rhetorical question (“For who can tell him …?”) is a negative affirmation, expecting a negative answer: “For no one can tell him …!” (see E. W. Bullinger, Figures of Speech, ). The translation renders this rhetorical device as a positive affirmation.

In other versions

ESVEnglish Standard Version

For who knows what is good for man while he lives the few days of his vain life, which he passes like a shadow? For who can tell man what will be after him under the sun?

NIVNew International Version (2011)

For who knows what is good for a person in life, during the few and meaningless days they pass through like a shadow? Who can tell them what will happen under the sun after they are gone?

CSBChristian Standard Bible

For who knows what is good for anyone in life, in the few days of his futile life that he spends like a shadow? Who can tell anyone what will happen after him under the sun?

NLTNew Living Translation

In the few days of our meaningless lives, who knows how our days can best be spent? Our lives are like a shadow. Who can tell what will happen on this earth after we are gone?

LEBThe Lexham English Bible

For who knows what is good for a man in his life during the few days of his fleeting life, which are fleeting as a shadow? For who can tell anyone what will happen in the future under the sun?

KJV 1900King James Version

For who knoweth what is good for man in this life, all the days of his vain life which he spendeth as a shadow? for who can tell a man what shall be after him under the sun?

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