Question

【题目】To keep children away from danger, we warn parents ______ their children at home alone,
A.leave
B.to leave
C.not leave
D.not to leave

Answer 1

【答案】D
【解析】句意：为了让孩子们远离危险，我们警告家长不要把孩子单独留在家里。warn sb. (not) to do sth. 意为“警告某人（不）要做某事”。根据题意是警告家长不要把小孩子单独留在家中，其中否定词要放在不定式前面，即 not to leave 而不是 to not leave。故选D。