David jumped _____ to get the first ______ the beginning of the sports.

Twenty million years ago, Idoho was not the dry place as it is now. ______, it was warm and damp, covered with thick forests.

A man may usually be known by the books he reads _____ by the friends he keeps.

Make sure to turn off the gas after you take a bath, which would ___ cause danger.

I shall certainly not tell him the news. ________, it will go to his ears sooner or later.