Don't throw things at the monkeys.是Throw things at the monkeys.的否定句。

Throw things at the monkeys.是祈使句。祈使句的肯定句变否定句的规则是:

1、在动词原形前加don't.但是don't是否要大写，就要看看它是否位于句首。例如:Listen to the music.->Don't listen to the music.

Please draw on the wall.->Please don'tdraw on the wall.

2、no＋名词或者动名词。例如:No food. No smoking.这种否定句是禁止的意思。