― I'm afraid I have to give it up.
― Don't be discouraged. Remember ______ sticks to his work will succeed one day.
| A．those who | B．who | C．whoever | D．whomever |
_______from the moon, our earth, with water _____about 70 percent of its surface, appears like a blue ball.
| A．Seen; covered | B．Seeing; covering |
| C．Seen; covering | D．Seeing; covered |
---Have you got any particular plans for the coming holiday?
---Yes. __________, I’m going to visit some homes for the old in the city.
| A．If ever | B．If busy | C．If so | D．If possible |
---Have the arrangements for the concert next Saturday been all _______?
---Not yet. We haven’t found a free hand.
| A．in store | B．in trouble | C．in turn | D．in place |
___________in the mountain for a week, the students were finally saved by the local police .
| A．Having lost | B．Lost | C．Being lost | D．Losing |
There are some health problems that, when ____ in time, can become bigger ones later on.
| A．not treated | B．not being treated |
| C．not to be treated | D．not having been treated |