8.词素的类别和使用How many morphemes are there in the English language? state what they are and illustrate how they work?
⑴there are two: free and bound morphemes.
⑵free morphemes are independent units of meaning and can be used freely all by themselves.
⑶bound morphemes are those that cant be used independently but have to combined with other morphemes.
⑷either free or bound, to form a word, it includes 2types:
A root is often seen as part of a word,it can never stand by itself although it bears clear, definite meaning, it must be combined with another root  or an affix to form a word.
⑸Affixes are morphemes that are added to an already existing morpheme to form a new word while changing its meaning and grammatical relations. it consists of both inflectional and derivational affixes,
9.语言的两种功能two functions of language?
Two major functions are interpersonal and intrapersonal communication.
人际交流和自我交流
⑴ language functions as a means of interpersonal communication when language users use it to convey information, thoughts and feelings from one person to another or to control each other’s behavior.
⑵ it functions as a means of intrapersonal communication when it is used as a means of facilitate thinking, speech behavior and action for the individual.
10.为什么说结构树形图比线形图可更好的说明句子的层次性？why do we say tree diagrams are more advantageous and informative than linear structure in analyzing the constituent relationship among linguistic elements?
⑴in addition to revealing a linear order, a constituent structure tree has a hierarchical structure that groups words into structural constituents and shows the syntactic category of each structural constituent, and consequently is believed to most truthfully illustrate the constituent relationship among linguistic elements.
线形结构无法解释或说明有歧义的句子。
⑵for example, the phrase ”the old men and women” may have two interpretation. The adject ”old” may modify the noun ”men ”,or the “women”. or both. linear order analysis cannot tell this difference, so it’s ambiguous. the constituent of tree diagrams analysis can make this difference clear.
11.音素、音位、音位变体的定义及关系Explain with examples 3notions of phone, phoneme and allophone, how they are related.
⑴A phone is a speech sound, it is a phonetic unit. any sound we hear in the course of communication is a phone, such as [ u:],[ l ];
⑵A phoneme is a phonological unit, it’s not a concrete sound but an abstract notion, it’s a collection of features. it can be realized as different phones in different phonetic contexts. Such as ,the phoneme[ l ] can be realized as a clear[ l ] or a dark [ l ],depending on where it occurs in a sound combination.
⑶The actually phonetic realization of a phoneme are called its allophones, allophones are the actual phones we hear in linguistic communication.