That is 还是that are

这个要分情况的啊，不能这么绝对，我举个例子M: This truck looks like what I need but I’m worried about maintenance. For us it’ll have to operate for long periods of time in very cold temperatures.W: We have several models thatare especially adaptive for extreme conditions. Would you like to see them?这里面that后就要接必动词are，接is就是错的。

典型的定语词句，that指定先行词models,models是个复数可数名词，models在定语从句里充当主语，所以要用必动词are。

英语中的that(那个）those (那些) this (这个) these(这些）统称为指示代词。this，that是单数，these those是复数.当这些词在句子中做主语时，主语和谓语动词再数上要保持一致。因此我们通常说this is (that is） 而不能说this are和that are.这是英语中约定俗成的一个语法规则。

用that is，例如：

1.To an extent, that is the reason for the meeting.在某种程度上，那就是召开这次会议的原因。

2.I'm not suggesting that is what is happening.我没有说那就是事实。

3.If that is the case, we need more staff.如果真是那样，我们就需要更多的员工了。