It was____the old worker came that we____the experiment.
| A．until;didn’t begin | B．not until;began |
| C．until;began | D．not until;didn’tbegin |
_______ you don’t stay out too late, you may go to the party. But remember to be back here no later than 11:30 pm.
| A．Now that | B．Until | C．Provided that | D．Although |
Unfortunately, when I dropped in, Dr. Green ______, so we only had time for a few words.
| A．just left | B．has just left | C．had just left | D．was just leaving |
The animal makes a strange sound, slightly ______ the bark of a dog.
| A．resembling | B．requesting | C．resisting | D．reflecting |
You got back so late and you didn’t even give me a proper reason _______ you hadn’t called me! I’m very unhappy with you.
| A．when | B．why | C．how | D．which |
There was a big dog ______ in front of Mr. Hill’s house, so David didn’t dare to go near it.
| A．to sit | B．sat | C．sitting | D．sits |