Who is it up ________ decide whether to go or not?
—Your mother becomes more and more forgetful.—Yes. She searched for her cellphone for a whole day last Sunday but it ______ in her coat pocket the next day.
—Who______ it be that is knocking at the door?—It ______ be Father, but I’m not sure.
The letter he had been looking forward ____________ this morning.
He told ______ lie to his friends that he was heavily in _______ debt because he wanted to borrow some money from them.
―I’ve studied growing plants as one of my interests. Could I make some suggestions?―_____.