Do you remember ____when you heard about the important event?
Yes, I do
| A．what were you doing | B．what you were doing |
| C．what are you doing | D．what you are doing |
When we got to the hospital, Mary _______ there.
A. left B. has leftC. had left
Students are supposed _______ school uniforms on school days.
A. wear B. to wear C. wearing
—When ________ the telephone ________?
—In 1876.
A. is; invented
B. did; invented
C. was; invented
This dictionary______ Ellen’s. Look, her name is on it.
A. must be B. can’t be C. might be
The hall is ______ to hold one hundred people.
A. enough big B. big enough C. as big