'Happened' in the Bible

"'When a person sins in that he hears a public curse against one who fails to testify and he is a witness (he either saw or knew what had happened) and he does not make it known, then he will bear his punishment for iniquity.

It happened on the eighth day, that Moses called Aaron and his sons, and the elders of Israel;

But Aaron replied to Moses, “See, today they presented their sin offering and their burnt offering before the Lord. Since these things have happened to me, if I had eaten the sin offering today, would it have been acceptable in the Lord’s sight?”

And any person who touches anything that happened to be under him becomes unclean until the evening, and the person who carries them must wash his garments, and he shall wash [himself] with water, and he shall be unclean until the evening.