单选题 —Let me introduce the new professor to you.
—Mary: ___(　　)

单选题 The policeman told the children __(　　)__ play in the street.

单选题 Hardly ____ home when it started to rain heavily.

单选题 Not only ____ hard, but he also helped his classmates.

单选题 If I ____ you, I would accept the job offer without hesitation.

单选题 The problem is ___(　　)_ difficult for me ______ solve.

单选题 My father told me a story last night. It is ____ one I’ve ever heard.

单选题 In the past, it was a small stamp that helped family members and friends to (　　)each other.