Modal Verbs

I ......... go to see the doctor last week because I was very ill.
must
must to
had to

I could ......... bought that car but I didn't have enough money to pay for the petrol.
had
have
have to

I ......... go now because I am already late for my class.
must
had
have to

I may ......... able to come to your party if I have the time.
be
being
being to

Do you ......... clean the house every day or every week?
must
have
have to

I ......... speak French without a problem now because I have had many lessons.
may
can
have

They ......... do their homework today because it is a holiday at the school.
must not
don't have
don't have to

I ......... help you with your shopping because you have a lot of bags.
ought
ought to
thought

When will you ......... come and see us in our new house?
can
be able to
must

I may ......... go to Paris next week because there is a very big exhibition there.
have
have to
had