The letter “X” can be used ________ an unknown number.

A. to expressing     B. to express     C. expressing     D. expression

________ different kinds of pianos, the factory is sure they can satisfy people’s needs.

A. To produce           B. Being produced    C. Produced     D. Having produced

I first met Mr. Smith in America. He ________ at Stanford University then.

A. studied           B. had studied       C. is studying      D. was studying

On this map what does a star ________?

A. tell                        B. represent      C. say               D. mean

Tyron was very angry, but cool-headed enough to ________ rushing into the boss’s office.

A. prevent         B. avoid             C. protect          D. allow

Susan, ________ university student from Europe, teaches me ________ art in her spare time.

A. an; /               B. a; the              C. an; the             D. a; /

她可能成功。 (likely)

魯迅是中國的大作家之一。 (major)