The verb should be in the plural.

这个动词应该用复数形式。

《牛津词典》

Some nouns ending in 's' are only used in the plural.

有些以‘s’结尾的名词只有复数的形式。

youdao

That's why we speak of string theories in the plural, because there are several different string theories that attempt to make it all work.

这就是我们用复数形式来描述弦理论，因为现在有各种不同的弦理论，试图来解释所有的问题。

youdao

God ruminates that the humans have become like "one of us" in the plural.

上帝说到人类会变成“我们当中的一个“，时，用的是复数。

耶鲁公开课 - 旧约导论课程节选

Again in the plural. Who is he talking to?

用的也是复数，上帝在和谁说话？

耶鲁公开课 - 旧约导论课程节选

What the kind of regime that emerges along side the polis, is an aristocratic republic in which the noblemen have influence and power within the community by tradition and they are plural.

和城邦一同出现的政权制度,是一个贵族化的共和政体,贵族在城邦中依靠传统赋予他们的地位,发挥影响,拥有权力,他们的人数不止一个

耶鲁公开课 - 古希腊历史简介课程节选

Edinburgh Festival is a singular event most accurately referred to in the plural.

BBC: Edinburgh: Not just a pretty festival

The participants to the meeting hence decided to acknowledge the existence of such a movement, yet suggesting putting it in the plural tense.

UNESCO: MEDIA SERVICES

Ms. SUSAN YANG(ph): My name is Susan Yang, and the worst gift, in plural, I would have to say, are probably are those of--although I love chocolate and candy--those are probably the worst kinds of gifts because it's just temptation looking me in the face every day.

NPR: The Worst Gift Ever