And who knows whether that person will be wise or foolish? Yet they will have control over all the toil into which I have poured my effort and skill under the sun. This too is meaningless. (NIV)
And who knows whether he will be a wise man or a fool? Yet he will have dominion over all my labor in which I have toiled and in which I have shown myself wise under the sun. This is also vanity (emptiness, falsity, and futility)! (AMP)
And who knoweth whether he shall be a wise man or a fool? yet shall he have rule over all my labour wherein I have laboured, and wherein I have shewed myself wise under the sun. This is also vanity. (KJV)