英語句子的成分共九類,其中最主要的句子成分包括：主、謂、賓、表、定、狀、補語和同位語。
1、主語 (Subject) 是句子的核心,是人或事。
(a) 位置：通常位於句子的開頭或位於謂語動詞前,表明動作的主體。
(b) 可以作主語的成分包括：名詞、代詞、數詞、主語從句(what/that/ how/ whether從句等)、現在分詞(-ing) 和動詞不定式(to do)、the + adj.結構。
(c) Study the following examples and underline the subject in each sentence.
Eg1. An earthquake has claimed hundreds of lives.
Eg2. Whether the football game will be played depends on the weather.
Eg3. The ignorant can be fearless.
2、謂語 (Predicate) 用來描述主語的動作、狀態或特徵。
(a) 位置：通常緊接著主語。
(b) 可以作謂語的成分包括：動詞、情態動詞+動詞。
(c) Study the following examples and underline the predicate in each sentence.
Eg1. Life is full of ups and downs.
Eg2. You cannot control your life, but you can control your attitude towards life.
Eg3: In this day and age, an increasing number of people agree that gambling (賭博) is an unwholesome hobby.
3、賓語 (Object) 用來表示動作或行為的物件。
(a) 位置：位於及物動詞或介詞後面。
(b) 可以作賓語的成分包括：名詞、代詞、數詞、複合結構(雙賓語等)、從句(what/that/ how/ whether從句等)、現在分詞、動詞不定式。
(c) Study the following examples and underline the object in each sentence.
Eg1. Junk food impairs people’s health.
Eg2. Change what you can bear, while bear what you cannot change. Eg3. Studies reveal that there is a definite link between obesity (肥胖症) and serious diseases such as heart attacks.
4、表語 (Predicative)。
(a) 位置：位於be動詞或系動詞 (如：look, seem, 詳見《講義》P8)。
(b) 可以作表語的成分包括：名詞、代詞、數詞、形容詞、副詞、介詞短語、現在分詞、過去分詞、動詞不定式或從句(what/that/ how/ whether從句等)。
(c) Study the following examples and underline the predicative in each sentence.
Eg1. Life is a stage.
Eg2. I feel under the weather today.
Eg3. What we should do is to teach children how to distinguish good from bad (right from wrong).
5、定語 (Attribute) 用來修飾名詞或名詞性片語。
(a) 位置：通常位於名詞或名詞性片語之前,有時也可放在之後(I want something to eat)。
(b) 可以作定語的成分包括：形容詞(最常用)、代詞、數詞、名詞、名詞所有格、介詞短語、現在分詞、過去分詞、動詞不定式和定語從句。
(c) Study the following examples and underline the attribute in each sentence.
Eg1. A warm smile is the universal language.
Eg2. In recent years, the Internet has been gaining in popularity at an amazing rate/ at lightning speed.
Eg3. Those who have spent some time earning a living or traveling to other places, have a broader view of life.
6、狀語 (Adverbial) 用來修飾動詞、形容詞、副詞或整個句子。
(a) 位置：通常位於動詞、形容詞、副詞或句子的前後。
(b) 可以作狀語的成分包括：副詞(最常用)、介詞短語、名詞、動詞不定式、現在分詞、過去分詞、狀語從句和狀語從句省略結構。
(c) Study the following examples and underline the adverbial in each sentence.
Eg1. Outdoor activities can greatly improve our health.
Eg2. Compared with the corresponding period last year, imports in the first three months have increased by 10 per cent
Eg3. When I was young, I was a troublemaker.
7、補語 (Complement) 對於主語或賓語進行補充說明。
(a) 分為主語補足語(補充說明主語的性質或狀態)和賓語補足語(補充說明賓語的性質或狀態)。
(b) 在雅思寫作中,主要的賓補結構主要是雙賓語結構。
(c) Study the following examples and underline the complement in each sentence.
Eg1. I regard you as my best friend.
Eg2. The graduates find the job market frustrating because of the economic recession.
Eg3. The advent of information age makes technical knowledge more crucial than ever.
8、同位語 (Appositive) 表明句子中的一個成分與另一成分表達同一概念,即A＝B。
(a) 可以作同位語的成分包括：名詞、代詞、數詞、形容詞、介詞短語、從句、動詞不定式和現在分詞。
(b) Study the following examples and underline the appositive in each sentence.
Eg1. We should ask Jim, the monitor, to be punctual.
Eg2. Job satisfaction, a very important part of an employee’s sense of well-being (幸福,安寧), can be promoted in most jobs. Eg3. All countries, big or small, should be treated equal.
9、補充解釋。
（）主謂賓結構為一種文法的語序，即語法順序為主語—謂語—賓語的結構，像英文的I eat apples就是一個例子，在此範例中I為主詞（主語，人），eat為動詞（謂語動詞），apples為名詞（賓語，物）。所以也可以理解為兩物（或一人一物）一動作為主謂賓結構。
（2）主語是句子敘述的主體，可由名詞、代詞、數詞、名詞化的形容詞、不定式、動名詞和主語從句等來承擔。
（3）謂語說明主語所發出的動作或具有的特徵和狀態。謂語由動詞來承擔。
（4）賓語是動作的物件或承受者，常位於及物動詞或介詞後面。賓語可由名詞、代詞、數詞、名詞化的形容詞、不定式、動名詞、賓語從句等來擔任。
（5）主謂結構：I run 謂語一般是不及物動詞，後面不加賓語。
（6）主謂賓結構：I play basketball這裡的謂語是及物動詞後面加賓語。
（7）主謂加雙賓：I give you a book這裡的you.book都是賓語。