第34题: [单项选择]______ sheep was grazing on the hill and an eye dog was watching them from a far. A. A herd of B. A school of C. A pair of D. A mop of 参考答案:A 答案解析:短语辨析。原句意为:一群羊在山坡上吃草,牧羊狗在远处看守着。首先排除C,B.a school of指鱼群 D. a mop of指一群暴徒,a herd of指一群动物,它们的谓语动词需要用单数。