这三个句子应用单数动词还是复数动词?

有一读者问: 下面三个句子应用复数动词还是单数动词:

(1)No one except his supporters_________with him. (agree)

(2)One in ten_________the medicine. (take)

(3)A bunch of keys_________found on the desk. (be)

句(1)应填复数形式agree,因为它属于概念上的一致。除用作主语的no one外,nobody和none用作主语时也常可用复数动词。

句(2)的上下文不详。one in ten如意谓“平均十个人当有一人”,则可用take。

句(3)中的a bunch of keys可用单形is(或was), 亦可用are(或were)。如强调a bunch的整体概念, 即应用单形动词; 如强调一个个的keys, 则应用复形动词。英语里既可用单形动词亦可用复形动词的名词除bunch外, 还有很多, 如group, crowd, gang, flock, herd, breed, band, batch, cluster等。