___ annoys me is that Kirn never returns the books she borrows on time.
| A．This | B．It | C．What | D．That |
He is ready to help others, seldom, ______ refusing them when they turn to him.
| A．if never | B．if ever | C．if not | D．if any |
Robert is said ______ abroad, but I don’t know which country he studied in.
| A．to have studied | B．to study | C．to be studying | D．to have been studying |
I can remember very few ______ when he had to cancel his plans because of poor health.
| A．situations | B．conditions | C．occasions | D．circumstances |
He hurried to the booking office only ______ that all the tickets had been sold out.
| A．to tell | B．to be told | C．telling | D．told |
They are just college graduates and don’t realize _____ to start and run a company.
| A．what takes it | B．what they take | C．what takes him | D．what it takes |