Radium salts, which have been found to _____ in bones, give rise to cancers of the bone.
| A．pile up | B．build up | C．keep up | D．pull up |
It’s hard to avoid mistakes. _____ we realize our mistakes and do our best to correct them, that’s all right.
| A．As if | B．As long as | C．Even if | D．In order that |
--- Oh, no! It’s ten to seven already and I’ll be late.
--- _____ . That clock is half an hour fast. You have enough time to go there.
| A．Hurry up | B．Look out | C．Watch out | D．Don’t worry |
Cindy and Tom like singing and dancing, but _____ students in the class go in for sports.
| A．others | B．the others | C．the other | D．another |
Do you know why _____ penguins living on _____ South pole are so popular with children?
| A．the; the | B．/ ; the | C．the; / | D． / ; / |
If you plant watermelon seeds in the spring, youfresh watermelon in the fall.
| A． | eat | B． | would eat | C． | have eaten | D． | will be eating |