.We will learn how to operate the machine _______.
I really can't understand _ ___ her like that.
It was a pity that the great writer died _____his works unfinished.
Playing tricks on others is___we should never do
He accidentally ___ he had quarreled with his wife and that he hadn't been home for a couple of weeks.
I don't _ ___ rock 'n' roll. It's much too noisy for my taste.