No sooner _________ he sat down to read the newspaper _________ the bell rang.
| A．do; when | B．did ； than |
| C．had ； then | D．had ； than |
— When do we need to pay the balance?
— ____ September 30.
| A．In | B．By | C．During | D．Within |
______ and out of breath, we reached the top of the mountain and stopped _____ the beautiful scenery.
| A．Tiring, to admire | B．Being tired, admiring |
| C．Tired, to admire | D．Tired, admiring |
I greeted the teacher with “ hello”, and the teacher gave me a sweet smile ______.
| A．by turns | B．in return |
| C．in turn | D．for turn |
Do you know the trouble he had _____ the work?
| A．on finishing | B．to finish |
| C．having finishing | D．finishing |
A communicative satellite ______ as much as 3.5 tons was sent up into space last week.
| A．weighing | B．weighed |
| C．to be weighed | D．being weighed |