【问】 Cattle were allowed to graze on the village common. cattle是个单数名词，为什么其谓语动词要用复数呢?

【答】 cattle，如同people和police一样，是个无标记复数名词，因此其谓语动词照例要用复数：

1. All his cattle were grazing in the field.

他所有的牛都在田野里吃草。

2. He has 20 cattle on the farm.

他农场里有20头牛。

3. These cattle are from Holland.

这些牛是从荷兰来的。

poultry作“家禽”解时，也是个无标记复数名词：

1. The poultry are being fed.

家禽正在吃食。

2. Our poultry are kept at the bottom of the garden.

我们的家禽养在花园的尽头。