There will be fines for people who drop litter.

乱扔垃圾的人将被罚款。

《牛津词典》

It was drilled into us at an early age never to drop litter.

我们从小就被叮嘱绝不能乱扔垃圾。

《牛津词典》

Some parents are concerned that it encourages their children to drop litter so they can watch the birds pick it up.

一些家长担心这样会鼓励他们的孩子乱扔垃圾，因为这样他们就可以看到鸟儿捡垃圾了。

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Rather than telling citizens they must not drop litter, it seems to be saying they should pick it up.

BBC: Should we pick up other people's litter?

This, one assumes, is more than reminding people of their legal duties not to drop litter or let their dog foul the pavement.

BBC: Should we pick up other people's litter?

Barry Anderson, Conservative councillor for Adel and Bramhope, said it was time for people who drop litter to be given "a short, sharp shock".

BBC: Leeds City Council uses security staff as litter wardens