While I _______ my bedroom, Joe called and said he wanted me to go boating with him.
| A．clean | B．am cleaning |
| C．have cleaned | D．was cleaning |
A. total B. top C. notice
The full moon often makes her _________ her hometown.
A. missing B. to miss C. miss
All the students in my class can’t ______ the math problem. It’s too difficult for us.
A. work on B. work out C. work for
My father was watching TV ______ my mother was cooking.
A. while B. until C. when
She will call you if she ____.
A. goes to B. come back C. comes back