About_____ of the earth__ __covered with water, but we have less and lessavailable fresh water.
| A．three-fourth, is | B．three-fourths, is |
| C．three-fourth, are | D．three-fourths, are |
Do you know the girl _________ is singing in the classroom?
A. when B. who C. which
Don’t talk loudly at the meeting. If you ________, you will have to leave.
A. do B. are C. did
—____________________?
—He is tall.
A. How is he B. What does he look like C. What does he like
I often go to school ________.
A. by bus B. by a bus C. by the bus
—How's it going?—.
A. It's great b. You are welcome c. Thanks a lot