—I’m busy with my schoolwork these days.
—That’s great! You won’t get good grades ______ you work hard.
| A．if | B．because |
| C．unless | D．after |
About seventy percent of our earth _______ by water.
| A．is covering | B．is covered |
| C．are covered | D．are covering |
Don’t worry about your boy. His temperature will ______ back to normal（正常）if he takes this medicine.
| A．drop | B．rise | C．go | D．travel |
Don’t ______ until the bus stops. Or it’s too dangerous.
| A．get it on | B．get into it |
| C．get off it | D．get it off |
Mr. Smith was ill ______. He had to have three weeks ______.
| A．in hospital, off | B．in the hospital, rest |
| C．in hospital, rest | D．in the hospital, off |
Paul made a nice cage ______ the little sick bird till it could fly.
| A．keep | B．kept | C．keeping | D．to keep |