下列各句中划线的成语使用不恰当的一句是（ ）

Should people stop using their cars and start using public transport?— __________ The roads are too crowded as it is

The key to_____ the problem is to meet the demand_____ by the customers. [ ]

Mary kept weighing herself to see how much _______ she was getting.

This girl is ready to help peopleany time. When she is on the bus, she always herseat to someone in need.