Speech acts can be divided into three levels:the first level is the locutionary act,which means that words express meaning;the second level is the illocutionary act,which means that words express the specific intention of the speaker;and the third level is the perlocutionary act,which means that words have a certain effect.The function and meaning of Chinese modal particles have always been a difficult issue to characterize,whether in the generalizing or decomposing mode.It is diffi-cult to accurately and fully describe the function and meaning of modal particles in any model.Starting with speech acts to study the function and meaning of modal particles is a new attempt.