Whatever exists has already been named, and what humanity is has been known; no one can contend with someone who is stronger.
NIV
Whatever [man] is, he has been named that long ago, and it is known that it is man [Adam]; nor can he contend with Him who is mightier than he [whether God or death].
AMP
That which hath been is named already, and it is known that it is man: neither may he contend with him that is mightier than he.
KJV
All their days their work is grief and pain; even at night their minds do not rest. This too is meaningless.
NIV
For all his days are but pain and sorrow, and his work is a vexation and grief; his mind takes no rest even at night. This is also vanity (emptiness, falsity, and futility)!
AMP
For all his days are sorrows, and his travail grief; yea, his heart taketh not rest in the night. This is also vanity.
KJV
They seldom reflect on the days of their lives, because God keeps them occupied with gladness of heart.
NIV
For he shall not much remember [seriously] the days of his life, because God [Himself] answers and corresponds to the joy of his heart [the tranquillity of God is mirrored in him].
AMP
For he shall not much remember the days of his life; because God answereth him in the joy of his heart.
KJV