主語與動詞的基本配合
一般現在式中，he、she、it 及單數名詞作主語時，主要動詞通常加 -s 或 -es；I、you、we、they 及複數名詞則用原形。be 及 have 有各自的變化。
| 主語 | 一般動詞 | be / have |
|---|---|---|
| I | I read every evening. | I am ready. / I have a question. |
| you / we / they | They read every evening. | They are ready. / They have a question. |
| he / she / it / 單數名詞 | My cousin reads every evening. | She is ready. / She has a question. |
| 複數名詞 | My cousins read every evening. | The students are ready. / The students have questions. |
主語與動詞之間有其他詞語時
介詞片語及其他修飾語不會自動改變主語的單複數。判斷時應先辨認主語的核心名詞，再選擇動詞形式。
| 原創例句 | 主語 | 判斷依據 |
|---|---|---|
| The box of pencils is on the shelf. | The box | of pencils 修飾 box；核心名詞 box 是單數。 |
| The students in the front row are quiet. | The students | in the front row 說明位置；students 是複數。 |
| There is a notice on the board. / There are two notices on the board. | a notice / two notices | there be 結構須按後面的名詞選擇 is 或 are。 |
不定代詞及數量表達
| 表達方式 | 常用配合 | 原創例句 |
|---|---|---|
| everyone / somebody / each | 通常配合單數動詞。 | Everyone needs a ticket. / Each of the rooms has a window. |
| a number of + 複數名詞 | 表示若干人或事物，配合複數動詞。 | A number of students are absent. |
| the number of + 複數名詞 | 指人或事物的數目，配合單數動詞。 | The number of students is increasing. |
| 不可數名詞 | 一般配合單數動詞。 | The information is useful. / This equipment needs repair. |
集合名詞及部分數量結構的配合，可能因語意或英美式習慣而異；以上整理的是常見校內用法。
主謂一致與時態的關係
第三身單數加 -s 的規則主要用於一般現在式。一般過去式的大部分動詞，不會因主語單複數而改變形式；be 動詞的 was、were 則須另外判斷。
She walks home. / They walk home.
She walked home yesterday. / They walked home yesterday.
She was tired. / They were tired.
疑問句或否定句使用 does、did 等助動詞時，主要動詞用原形；情態動詞後亦用原形，例如 She can swim，不能再加 -s。
編製說明及延伸閱讀
本頁的知識說明及應用例子由耀星教育中心整理。資料供日常溫習參考，實際學習及考試範圍，請以學校的教學安排為準。