情态动词表示说话人的情绪、态度或语气。怎么样来理解，能否举例说明下什么表示情绪，什么表态度或语气？另按句法功能分，情态动词是动词的一种。时态，语态和语气是动词的一种形式，他们与动词之间算是什么关系呢？

不知网友关于情态动词的概念来自什么地方。假如此概念并不准确，随后的提问则没意义。

以下为《维基百科》对情态动词modal verb的概念与情态动词的语义功能的说明。


Amodal verbis a type ofverbthat is used to indicatemodality– that is: likelihood, ability, permission, request, capacity, suggestions, order and obligation, and advice etc. They always take v1 form with them.[1]Examples include the English verbscan/could,may/might,must,will/wouldandshall/should. In English and otherGermanic languages, modal verbs are often distinguished as a class based on certain grammatical properties.

Function

A modal auxiliary verb gives information about the function of the mainverbthat it governs. Modals have a wide variety of communicative functions, but these functions can generally be related to a scale ranging from possibility to necessity , in terms of one of the following types of modality:

epistemic modality, concerned with the theoreticalpossibility of propositions being true or not true

deontic modality, concerned withpossibility and necessity in terms of freedom to act

dynamic modality,[2]which may be distinguished from deontic modality in that, with dynamic modality, the conditioning factors areinternal– the subjects own ability or willingness to act[3]

The following sentences illustrate epistemic and deontic uses of the English modal verbmust:

epistemic:Youmustbe starving.

deontic:Youmustleave now.

An ambiguous case isYou must speak Spanish.The primary meaning would be the deontic meaning but this may be intended epistemically Epistemic modals can be analyzed asraising verbs, while deontic modals can be analyzed ascontrol verbs.

Epistemic usages of modals tend to develop from deontic usages.[4]For example, the inferred certainty sense of Englishmustdeveloped after the strong obligation sense; the probabilistic sense ofshoulddeveloped after the weak obligation sense; and the possibility senses ofmayandcandeveloped later than the permission or ability sense. Two typical sequences of evolution of modal meanings are:

internal mental ability → internal ability → root possibility → permission and epistemic possibility

obligation → probability