如果你不把牛奶放进冰箱，它会变质的。

That milk will ___go ___off if you don't put it in the fridge.

我们不得不投诉牛奶，因为它已经变质了。

We had to complain about the milk because it had ___gone ___off.

面包因为湿度大，仅两天就变质了。

The bread ___went ___off after just two days because of the humidity.