為什麼要有定語狀語表語補語

這是對句子結構進行分析所需要。即不同的詞類做什麼語法作用，它們的結構和序列又是怎麼樣的，這些需要進行科學地歸納出規律。

1、定語：限定名詞/代詞的詞語。位置可在名詞的前或後。能作定語的詞語有：

形容詞：Victoria is a beautiful city in Canada.

名詞：This is an apple tree.

數詞：There are thirty teachers in our school.

介詞短語：Tom is reading an article about gardening.

不定式短語：She is always the first to come to the office.

分詞短語：China is a developing country America is a developed country.

動名詞短語：The teaching plan for next term has been worked out.

定語從句：The man who is shaking hands with my father is a policeman.

Liquid water changes to vapor， which is called evaporation.

2、狀語：修飾動詞的詞語（也修飾形容詞、副詞或句子）。位置比較靈活。狀語的種類有十一種：時間、地點、方式、原因、目的、結果、比較、讓步、條件、程度、伴隨狀語。能作狀語的詞語有：

副詞：He run very quickly.（方式狀語）

形容詞：He lay in the bed， awake.

現在分詞短語：He is in the room， making a model plane.（伴隨狀語）

Walking in the street， I met my daddy.（時間狀語）

Not knowing the way to the school， they are worried. （原因狀語）

過去分詞：Seen from space， the earth looks blue. （條件狀語）

He left the room， followed by his wife.（伴隨狀語）

The professor is sitting in a chair， surrounded by students. （伴隨狀語）

不定式短語：Tina is proud to have passed the final exam.（原因狀語）

I need a dictionary to learn English well.（目的狀語）

介詞短語：She has lived in the city for six years.（時間狀語）

名詞短語：Wait a minete.（時間狀語）He works hard day and night.（方式狀語）

狀語從句：I didn't attend the party because it rained.（原因狀語從句）

He got up early so that he could catch the first bus.（目的狀語從句）

Peter will go there if it doesn't rain.（條件狀語從句）

3、補語：補充或説明其前面的名詞的詞語。分賓語補語和主語補語。賓語補語：有些及物動詞，除了要有賓語，還要在賓語後面跟上賓語補語，構成複合賓語，才能使句子意思完整。如果這類句子變成被動語態，賓語成為主語，則原賓補相應變為主補。做補語的詞語有：

名詞：His father named him Daming.

形容詞：They painted the wall white.

副詞：Let the fresh air in.

現在分詞：I heard Tom singing in the classroom.

過去分詞：I have my house repaired.

不定式：My mom wants me to be a doctor.

從句：We will soon make our city what your city is now.

現在分詞做主補：Jean was heard singing by me this morning.

介詞短語做主補：Everything was found in good order by us.

4、表語：表達主語的特徵或者性質的詞語。位置在系動詞後面（倒裝除外系動詞有六類）。作表語的詞語有：

名詞：Our Math teacher is a Canadian.

代詞：Is it yours?

形容詞：The weather has turned cold.

副詞：Time is up. The class is over. I am off.

現在分詞：The speach is exciting.

過去分詞：I am excited.

動名詞短語：My hobby is playing table tennis.

不定式短語：My job is to tach English.

介詞短語：The machine must be out of order.

表語從句：The truth is that he has never been abroad.

5、它們的從句：用一個句子做上述成分（“語”），就是對應“語”的從句。這個從句可以含有自己的從句，這就形成了從句的嵌套。舉例説明（斜體加粗部分為從句，但下面的從句裏都沒有嵌套從句）：

限定性定語從句：The manwho is shaking hands with my father is a policeman.

非限定性定語從句：Liquid water changes to vapor， which is called evaporation.

原因狀語從句：I didn't attend the party because it rained.

目的狀語從句：He got up early so that he could catch the first bus.

條件狀語從句：Peter will go thereif it doesn't rain.

表語從句：The truth is that he has never been abroad.

補語從句：We will soon make our city what your city is now.（注：這是賓語補語從句。很少有人講“補語從句”）