'Unless' in the Bible

Do two walk together unless they have met?

Does a lion roar in the forest {when he has no prey}? Does a fierce, young lion cry out from his den unless he has caught [something]?

Does a bird fall into a trapping net on the earth when there is no snare for it? Does a trapping net spring up from the ground unless it has certainly caught something?

Surely my Lord does not do anything unless he has revealed his secret to his servants the prophets.