The discovery was a major ............. for research workers
A.break-in
B.break-out
C.break-through
D.break-down

Choose the correct answer to the following questions.
When I first went to England, I _____________ English, but I _____________ it.
A.can read / can’t speak
B.can read / couldn’t speak
C.could read / couldn’t speak
D.could read / can’t speak

Choose the correct answer to the following questions.
“Did you hear me come in last night?” - “No, I _____________ asleep.”
A.must be
B.must have been
C.should be
D.should have been

Choose the correct answer to the following questions.
When the fog lifts, we _____________ where we are.
A.could see
B.will be able to see
C.must have seen
D.are seeing

Choose the correct answer to the following questions.
You _____________ ring the bell; I have a key.
A.may not
B.needn’t
C.mustn’t
D.couldn’t

Choose the correct answer to the following questions.
She felt ill and _____________ leave early.
A.has to
B.must
C.had to
D.ought

Choose the correct answer to the following questions.
“I heard their phone ringing.” - “You _____________ hear phone ringing. They don’t have a phone.”
A.couldn’t
B.shouldn’t
C.mustn’t
D.needn’t

Choose the correct answer to the following questions.
He helped her, but it was not necessary. He needn’t _____________ her.
A.help
B.to help
C.be helping
D.have helped

Choose the correct answer to the following questions.
I’m feeling very tired this morning. I _____________ have stayed up late last night.
A.couldn’t
B.shouldn’t
C.mustn’t
D.to stopping

Choose the correct answer to the following questions.
The fortune teller predicted that she_____________ inherit a big fortune before the end of this year.
A.must
B.will
C.would
D.would like