There are certain _______when you have to interrupt people who are in the middle of doing something.
| A．chances | B．situations | C．occasions | D．opportunities |
China’s police authority banned on drink driving，aimed______serious traffic accidents.
| A．to preventing | B．at preventing | C．preventing | D．prevented |
—as your former classmate come back from the USA?
—Yes, he ____ there for eight years.
| A．has stayed | B．stays | C．stayed | D．had stayed |
____ is no doubt ____ our class will win the first prize in the final match.
A, It; whether B. There; that C. It; that D. There; whether
Although he knew little about the large amount of work done in the field, he succeeded ________ other more well - informed experimenters failed.
| A．which | B．that | C．what | D．where |
—Is the experiment easy?
— ________ . I’ll just do my bit.
| A．I think so | B．Certainly | C．Not a little | D．Anything but |