Measures have been taken to prevent the accidents, but much _____ for more improvement.
| A．remains to be done | B．is remained to do |
| C．remains to do | D．is remaining to be done |
—What's the matter with Della?
—Well，her parents wouldn't allow her to go to the party，but she still ________.
| A．hopes to | B．hopes so |
| C．hopes not | D．hopes for |
________ a certain doubt among the people as to the practical value of the project.
| A．It has | B．They have |
| C．It remains | D．There remains |
It sounds like something is wrong with the car's engine.________，we'd better take it to the garage immediately.(2011·江苏，33)
| A．Otherwise | B．If not |
| C．But for that | D．If so |
________ a strange plant！I've never seen it before.(2011·辽宁，33)
| A．Which | B．What | C．How | D．Whether |
—Why does the lake smell terrible?
—Because large quantities of water ________.
| A．have polluted | B．is being polluted |
| C．has been polluted | D．have been polluted |