新概念英语2册28课（No parking）问题
1．课文中其中有一句是（第三行末）when he returns home at night,he always finds thatsome one has parked a car outside his gate.这一句用的是一般过去式,为什么?而前面的几句都是现在完成时．
2．课后难点：
The man when you meet yesterday is an actor.
可以改成
The man you meet yesterday is an actor.
而
The pilot whose plane landed in a field was not hurt.
却不能改,为什么?