Tense and reference are two terms often encountered in the study of meaning.

判断题All words may be said to contain a root morpheme.

填空题Consonant sounds can be either （）or（）,while all vowel sounds are （）.

填空题To many people,a linguist is the same as a （）,one who can speak several languages fluently.

填空题Utterance is based on （）;it is the realization of the abstract meaning of a sentence in a real situation of communication,or simply in a context.

填空题In sociolinguistic studies,speakers are treated as members of（）.