______life began on the earth is one of the biggest puzzles to scientists.
| A．How | B．What | C．Where | D．That |
. You have a big mouth, Tom. You _______ have told everybody the secret.
| A．can’t | B．mustn’t | C．shouldn’t | D．mightn’t |
He’s not got another job yet and it’s not ______ he will for some time.
| A．likely | B．possibly | C．probably | D．easily |
We will ______ all the natural resources if we continue consuming them like that.
| A．run out | B．wipe out | C．drop out | D．hold out |
. She wasn’t a much older tennis player but he had the great ______ of experience about games.
| A．interest | B．advantage | C．benefit | D．profit |
. I wonder why Ann didn’t get ______ the job. She is the right person for it.
| A．to be offered | B．to offer | C．offering | D．offered |