We don’t doubt _____ he will succeed in the research work.
| A．that | B．whether | C．how | D．what |
Most scientists seem to agree that _______ certain limit should be set on _______consumption of cars to ease air pollution．
| A．a; the | B．/;the | C．the; / | D．the; the |
comb
| A．habit | B．debt | C．substance | D．above |
custom
| A．measure | B．upstairs | C．respect | D．sugar |
salt
| A．almost | B．calm | C．chalk | D．half |
singer
| A．single | B．language | C．stronger | D．bringing |