电影《情书》:a chain of...用作主语时，谓语用什么数

a chain of...用作主语时，谓语用什么数 a pair of sth. 作主语时，谓语动词的单复数，由哪个词决定？ Ruturn of The Chain Gang what the matter of a mountain is not its height中的主语疑问－[讨论] can you give an example of industry value chain? Which alkane can have a nanaoscale carbon chain ? 英语中分数+of+n.做主语时谓语是单数还是复数? the largest number of 作主语 a fork and knife作主语时，谓语动词是否用单数？ 宾谓主语