'Task' in the Bible

And I set my mind to seek and explore by wisdom concerning all that has been done under heaven. It is a grievous task which God has given to the sons of men to be afflicted with.

Because all his days his task is painful and grievous; even at night his mind does not rest. This too is vanity.

For to a person who is good in His sight He has given wisdom and knowledge and joy, while to the sinner He has given the task of gathering and collecting so that he may give to one who is good in God’s sight. This too is vanity and striving after wind.

I have seen the task which God has given the sons of men with which to occupy themselves.

There was a certain man without a dependent, having neither a son nor a brother, yet there was no end to all his labor. Indeed, his eyes were not satisfied with riches and he never asked, “And for whom am I laboring and depriving myself of pleasure?” This too is vanity and it is a grievous task.

When I gave my heart to know wisdom and to see the task which has been done on the earth (even though one should never sleep day or night),