变动型模糊限制语是指那些可以改变话语的词语。在言语交际中，说话人根据实际情况使用这类限制语，改变原来话语意思，达到交际目的。变动型模糊限制语又可分为两类： 程度变动语（adaptors）和范围变动语（rounders）。

程度变动语是指那些能揭示话语真实程度差别的词语。具体有这样一些常用的词和短语：sort of , a little bit, almost, entirely, kind of, more or less, quite, really, some, somewhat, to some extent，等等。使用这些词语可以把一些接近正确，但又不敢肯定完全正确的话说得更得体一些，更接近真实。

A: What about his ears? Is he still draining fluid? It's just sort of crusted, not really draining?

A: How did you like that film? I kind of like it?

Sort of, really, kind of 的使用修正了原话语的真实程度，削弱了句子的肯定语气，使话语更真实，更客观。

范围变动语是指限制变动范围的词和短语。具体有：about, around, approximately, essentially, in most respects, loosely/strictly speaking, par excellence, roughly, something between x and y, over,，等等。这类词往往和具体数字一起使用，听话人可以在一定的范围内去理解话语，不必讲究实际情况与话语的接近程度。例如：

His weight was approximately three point two kilograms, which is was essentially what his birth weight?

The baby's blood pressure was also about something between forty and fifty palpable?

当说话人不想把话说得太死，以免与事实有距离，或者因无法一下子说出一个准确的数字，于是就使用了范围变动语，让听话人在一定范围内去理解话语。在言语交际中正确使用程度变动语和范围变动语，可以避免说话武断，做到说话得体，从而顺利实现交际目的。

缓和型模糊限制语不改变话语结构的原意，话语中加上这类限制语相当于增加了一个说明，使原来话语的肯定语气趋向缓和。缓和型模糊限制语也可分为两类：直接缓和语（Plausibility Shields）和间接缓和语（Attribution Shields）。

直接缓和语是指表达说话人对话题的猜测或怀疑态度的词和短语。具体有：I think, as far as I know, as far as I can, seem, probably, wonder, hard to say, I believe, I assume, I suppose, I'm afraid, I guess, I suspect，等等。当说话人对话语的真实性信心不足，或没有把握给予肯定，就可以使用这些表示说话人猜测或怀疑的词，以缓和话语的肯定语气。例如：

I think we can probably finish the work before evening?

What he said is true, I guess?

间接缓和语也是为了表达说话人对话语的不肯定，但它是通过引用第三者的看法来间接表达自己的态度。具体有：according to one's estimates, as is well known, presumably, someone says that, it is said that, the possibility, would be…, the probability is …, it is assumed that …，等等。间接缓和语与直接缓和语的区别在与：直接缓和语直接表达说话人本人的怀疑态度，而间接缓和语则通过引用他人的观点来支持自己的观点，这就使话语显得更客观，也巧妙地避免因说话不准确时应承担的责任。例如：

According to her estimates, she got the baby's high heart rate back within two to three or so?

It was said that she would come back next week?

According to her estimates 和it was said that 是间接缓和语，而or so则是范围变动语。

从模糊限制语的分类可看出，由于交际目的的需要，说话人使用了不同的限制语，有时一个句子当中会同时出现不同类别的几种限制语。而且，有些模糊限制语的功能是多方面的只能根据语境来判断它们的类型（何自然，1988：159）。模糊限制语的广泛运用是言语交际的实际需要，必然符合语言运用的基本原则。下面用会话合作原则对其语用功能及意义进行详细的分析。