Be careful _ too fast, or there _ be an accident.
A. not to drive; must
B. to not drive; may
C. not drive; must
D. not to drive; may
网友回答
A. not to drive; must
B. to not drive; may
C. not drive; must
(答案→)D. not to drive; may
解析：本题的含义是当心开车不要开得太快，否则可能会发生交通事故。Be careful not to do表示当心不要做某事的意思，动词不定式的否定形式在to do前加not，may表示可能性或许的意思，故本题选D。