We __________ so tired. We've only been to a party.
| A．mustn't have felt | B．wouldn't have felt |
| C．shouldn't have felt | D．couldn't have felt |
We will work ____ we are needed.
| A．whenever | B．because | C．since | D．wherever |
Read it aloud _____ the class can hear you.
| A．so that | B．if | C．when | D．although |
_____ you go, don't forget your people.
| A．Whenever | B．However | C．Wherever | D．Whichever |
It is about ten years _____ I met you last.
| A．since | B．for | C．when | D．as |
They will never succeed, _____ hard they try.
| A．because | B．however | C．when | D．since |