I don’t suppose he is ______ to come to our help when we get into trouble.
| A．maybe | B．possible | C．likely | D．probable |
Each of the students, hoping to pass the exam, _____the book.
| A．buying | B．having bought | C．should buy | D．to buy |
He told me the news_____, believe it or not, he had earned $1 000 in a single day.
| A．that | B．which | C．as | D．because |
The research is so designed that once _____ nothing can be done to change it.
| A．begins | B．having begun | C．beginning | D．begun |
If _____ carefully, the experiment will be successful.
| A．do | B．does | C．done | D．doing |
----- When was the People’s Liberation Army’s Navy founded?
-----It ____the April of 1949.
| A．dates to | B．dated back | C．dated from | D．dates back to |