'Surely' in the Bible

Then I considered all the skillful work that is done: Surely it is nothing more than competition between one person and another. This also is profitless -- like chasing the wind.

Surely, he ate in darkness every day of his life, and he suffered greatly with sickness and anger.

Surely oppression can turn a wise person into a fool; likewise, a bribe corrupts the heart.

Surely the king's authority is absolute; no one can say to him, "What are you doing?"

Surely no one knows the future, and no one can tell another person what will happen.

Surely, no one knows his appointed time! Like fish that are caught in a deadly net, and like birds that are caught in a snare -- just like them, all people are ensnared at an unfortunate time that falls upon them suddenly.