第一单元英语词汇概说英语单词的结构⒈词word: It is a minimal free form of language which has given sound and meaning andsyntactic function. Eg: book, red …..⒉词条entry: It is a term used by dictionary compilers. It refers to all the information aboutword that appears in a dictionary.It includes the headword, the pronunciation, definition, irregular plural forms, comparative and superlative form, irregular forms of verbs, part of speeches, even derivatives of the headword, etc.⒊词位lexeme: In linguistic study, every entry (specifically the headword) which are collectedinto a dictionary is called a lexeme by linguists. An lexeme is an abstract unit in linguistics that roughly corresponds to a set of forms taken by a single word. Eg: run, runs, ran, running. 原形大写表示词位，词位相当于词条中的headword.⒋词形word form: Different forms of a word which are caused by the change of tense, number,point of view, part of speech, etc. are called word form.⒌词汇vocabulary/ lexicon: all the words in a language are termed as it. However, vocabularycan also be used to refer to all the words in a book or in a particular historical period of time, or in a dialet, or in a particular discipline, or eben to all the words that a person possesses.⒍词汇单位lexical unit/ item: is a single word or chain of words that are the basic elements of alanguage’s lexicon. Eg: cat, traffic light, take care of, by-the-way, it’s raining cats and dogs. The entire store of lexical items in a language is called its lexis(词库).Ⅱ、classification of English wordsBy origin: native words 本土词; loan words外来词.By use frequency: basic word stock基础词; non-basic word stock非基础词.By the level of usage: common words 常用词；literary words 书面词；colloquial words口语词；slang words 俚语；technical words 术语.By notion(function): content words 实义词；function words 功能词.Ⅲ、⒈词素morpheme: is the smallest meaningful linguistic unit of language, not divisible oranalyzable into smaller forms. Word is composed of morphemes. 词素是词的组成部分，是语言中语音和词义的最小结合体。
单词是由词素构成的。
（自由词素可以单独使用）⒉independence of morpheme⑴自由词素free morpheme：①have complete meanings in themselves and can be used as freegrammatical units in sentences.具有完整的词汇意义，能够单独构成一个词独立使用的词根。
②The free morpheme is also content morphemes or free roots（自由词根）, simple words. ③all monomorphic word(单词素词) are all constituted by free morpheme. ④those polymorphic words(多词素词) which is wholly made up of free morphemes are called compounds(复合词) .⑵粘着词素bound morpheme:bound to other morphemes to form words. They do not haveindependent semantic meaning; instead, they have attached meaning.具有一定意义，但不能单独存在，必须黏附在其他形式上的词素。
Include bound roots(粘着词根)and bound affixes.⒊semantic importance of morpheme 词素的两大类词根与词缀⑴粘着词根bound root：part of word that carries the fundamental meaning just like a free root. Itis a bound form and has to combine with other morphemes to make words.不能单独使用，必须与其它词素结合起来才能构成词，属于粘着形式.⑵词缀affixes: are forms that are attached to words or word elements to modify meaning orfunction.只有语法意义，没有词汇意义或者虽有一定的词汇意义，但在词中只表达次要的意义. It includes inflectional and derivational affix.①屈折词缀inflectional affix: 只有语法意义，没有词汇意义。
-s, -‘s, -ed, -er, -est ……②派生词缀derivational affix: 有一定的语义，也常能决定单词的词性。
Decided into prefix(前缀)and suffix（后缀）.自由词根……. 自由形式词根词素粘着词根派生词缀粘附形式词缀后缀屈折词缀⒋词素变体allomorph: is any of the variant forms of a morpheme as conditioned by position or adjoining sounds. 同一词素在不同的构词环境中可以有不同的变体。
⒌词根root: is a part of the word when all the affixes are removed.含有明确的词汇语义，在单词中表达主要的意义。
⒍词干stem: is any morpheme or combination of morpheme which an affix can be added. It can be equivalent to a root, and it can also be two or more roots.词干可以是一个root 或派生词或复合词。
第二单元基本构词方法一、派生法⒈派生法derivation：the word formation method in which prefixes and suffixes are added to roots or bound root and bound root combine to form new words. 派生词缀和词根结合，后者粘着词根和粘着词根结合构成单词的方法。
Derivative 派生词①Prefix + root + suffix ②bound root + bound root⒉⑴a free root based derivative①prefix + a free root ②a free root + suffix ③prefix + a free root + suffix④combining form + a free root⑵ a bound root based derivative①prefix + a bound root ②a bound root + suffix ③prefix + a bound root +suffix④combining form + combining form ⑤combining form + suffix⒊⑴polysemic meaning of prefix and suffix 多义性⑵synonymous meaning of prefix and suffix 同义性⑶different productivity of prefix and suffix 构词能力差异(不同的派生词缀在当代英语中构成新词的能力，即构词能力productivity，差异很大。
跟无构词能力的粘着词根结合在一起的派生词缀，一般都是没有构词能力。
⒋prefixes are classified on a semantic basis and suffixes on a grammatical basis.⒌⑴the classification of prefixes⑵the classification of suffixes 看笔记⒈compounding ( composition ) is word formation method in which more than one free morphemes are combined to form a new word.把两个或两个以上独立的词结合在一起构成新词的方法。