一全文逐句语法解读
本课围绕 辨认顾客，重点是 定语从句（who / which / that 引导），以及 who 与 which 在指人、指物时的区别。
¶ 1 · 由 who 引导的定语从句（句 2、7、9）
| 句子 | 语法点 |
|---|
| Who served you, sir? | 定语从句 先行词指人时用 who |
| He's the man who bought these books. | who 在从句中作主语 |
| The man who I served was wearing a hat. | who 在从句中作宾语，可省略 |
¶ 2 · 由 which / that 引导的定语从句（句 3、5、14）
| 句子 | 语法点 |
|---|
| The lady who is standing behind the counter. | 先行词指人用 who |
| The books which are on the counter. | 先行词指物用 which |
| Is this the man that you served? | that 既可指人也可指物，多用于口语 |
¶ 3 · 现在完成时与过去时（句 1、9、15）
| 句子 | 语法点 |
|---|
| I bought two expensive dictionaries here half an hour ago | half an hour ago 是过去时间，用过去时 |
| but I forgot to take them with me. | forget to do = 忘了做（还没做） |
| I recognize him now. | 一般现在时表此刻的状态 |
二固定搭配与重点词组
| 短语 | 用法与例句 |
|---|
| customer n. 顾客 | 本课对话人身份称谓，未在课文中作为句子成分出现。 |
| manager n. 经理 | 本课对话人身份称谓，未在课文中作为句子成分出现。 |
| forget to do sth. | 忘记做某事。forgot to take them with me。 |
| serve sb. | 接待、招待某人。Who served you, sir? |
| behind the counter | 在柜台后面。 |
| put on | 穿上、戴上。Would you put it on, please? |
三语法核心总结
核心语法
定语从句 who / which / that
- 定语从句：先行词指人用 who 或 that，指物用 which 或 that。
- 关系代词在从句中作宾语时可以省略：the man (who) I served。
- forget to do 表“忘记去做（还没做）”，与 forget doing（忘记做过）不同。
- 本课生词 6 个：customer、manager 为对话人身份称谓，已收入「固定搭配」表；其余 4 个全部嵌入课文句子，无遗漏。