1. I…swim very far these day, but ten years ago I…..swim from one side of the lake to the other.

a. couldn't, could
b. can, could
c. can't, could
d. could, couldn't

2. They didn't have any tomatoes in the first shop I went to, but I….to get some in the next shop.
a. could
b. couldn't
c. had to
d. was able

3. Hey! You…walk on the grass. Look at that sign.
a. mustn't
b. don't have
c. should
d. had to

4. It's going to rain, so you…your bags outside.
a. shouldn't to leave
b. had better not to leave
c. had better not leave
d. had better to not leave

1. I…swim very far these day, but ten years ago I…..swim from one side of the lake to the other.