The earth is years old.
| A．four thousands six hundreds | B．four thousand six hundred |
| C．four thousand and six hundred million | D．four thousand six hundred millions |
—Must I finish my homework before I go home?
—No, you ________. But you ________ finish it before tomorrow.
A.mustn’t, must
B. needn’t, must
C. needn’t, mustn’t
—Must we keep the window________ all the time? —No, you don’t have to.
A. open B. opened C. Opening
James is _______ boy.
A. a 18-month-old
B. an 18-months-old
C. an 18-month-old
Germs are very small. They can ________ the human body ________ the skin.
A. get up, across
B. get into, through
C. get into, across
If it ________ tomorrow, we will go to the zoo.
A. isn’t rain
B. doesn’t rain
C. won’t rain