Question

1选择 急！！！

I notice him ___ the teachers' office just now
A went into B go into C was going into D came out of

Answer 1

选B.
notice sb. doing sth.表示注意到某人正在做某事，只有一瞬间。
notice sb. do sth.表示注意到了某人做某事的全过程。
其余几项均有语法错误。

Answer 2

B notice sb do sth 注意到某人经常做某事或做过了某事

Answer 3

B go into