—We can’t be successful ________ we keep working hard.
—I agree with you.
| A.if | B.unless | C.because | D.when |
Jack spends much money on books ________ he is not so rich.
| A.though | B.when | C.if | D.because |
The thing that matters is not whether you fail or not, ________ whether you try or not.
| A.and | B.or | C.so | D.but |
--- When did your father come back last night?
--- He didn’t come back _______ he finished all the work.
| A.until | B.while | C.if | D.unless |
I was doing my homework _______ mother was cooking.
| A.when | B.while | C.as | D.what time |
Kate's dad is getting old. She will go back home to see him _____it is convenient.
| A.because | B.whenever | C.although | D.unless |
Learning to write is learning to think. You don’t know things clearly _______ you can write them down.
| A.unless | B.if | C.since | D.whether |
I thought the actor was famous, _________ none of my friends has ever heard of him.
| A.and | B.or | C.so | D.but |