—Who______ it be that is knocking at the door?—It ______ be Father, but I’m not sure.
I have no dreams ________ to have a happy life.
It was_________ back home after the experiment.
An example of them is fraud, a crime _______ money is stolen by cheating others.
Dr. Frank failed many times but he finally _____ to find a successful way to solve the problem.
--Where have you been? ---I got caught in traffic, otherwise I _______ here earlier.