1.he bought such a lot of books that he could not read them all.

=>he bought so

2.the doctor advised him to stay in bed for a few days.

=>he...

3.i regretted not telling him what happened last night.

=.i wish

we must be proud of our country.

=>we must pride

we couldn't swim because the sea was rough.

=>the rough sea

1.it is important for him to do well on his exam.

=>it is important that....

2.the children should be in bed by now.

=>it is time that...