New words：

decline [dɪˈklaɪn]
v.下降；减少；衰退；衰落
v.谢绝；拒绝（礼貌地）
n.下降；衰退；衰落

详细词源拆解：

前缀 de-：down 向下、往下
词根 clin：源自拉丁语 clinare = bend 弯曲、倾斜

组合逻辑：

→ de- (向下) + clin (倾斜)
→ 向下倾斜 → 下降；衰退；衰落
→ 引申义：弯身谢绝 → 谢绝；拒绝

词汇家族：

decline（下降；谢绝）→ incline（倾斜；倾向）→ recline（倚靠；躺下）

必记高频搭配

a decline in …在某方面下降

The report shows a decline in sales last quarter.

decline rapidly / sharply 快速 / 急剧下降

If we don’t take action, the number of tigers will decline rapidly.

in decline 在衰退中；在减少中

Many traditional skills are in decline as society develops.

decline an invitation 谢绝邀请（婉拒）

He had to decline the invitation because he had to prepare for exams.

decline to do sth 拒绝做某事（礼貌）

She declined to answer the personal question.

关键使用提醒

1.decline 有两个核心意思：下降 / 婉拒

2.表示 “拒绝” 时，比 refuse 更礼貌、正式，多用于邀请、建议、帮助。

3.固定搭配：in decline 在下降中

New words：

laptop [ˈlæpˌtɒp] n. 笔记本电脑

详细词源拆解：

由两个简单名词合成：lap + top
lap：n. （人坐着时的）大腿上部、膝部
top：n. 顶部、上面

组合逻辑：

→ 放在膝上（lap）使用的顶部设备（top）
→ 可以放在腿上用的微型电脑 → 笔记本电脑；便携式电脑

词汇家族：

laptop（笔记本电脑）→ desktop（台式电脑）→ tablet（平板电脑）

必记高频搭配

We can study online with a laptop.
A desktop is usually cheaper than a laptop.
In oversea, Tablet PC has already been applied in school.

New words：

`consumer [kənˈsumər] n. 消费者

必记高频搭配

consumers’ rights 消费者权益

We should protect consumers’ rights.

average consumer 普通消费者

The price is too high for the average consumer.

consumer goods 消费品

This factory makes daily consumer goods.

New words：

consumption /kənˈsʌmpʃn/ n. 消费；(能量、食物或材料的)消耗，消耗量；

必记高频搭配

fuel consumption 油耗；燃料消耗

This car has low fuel consumption.

energy consumption 能源消耗

We should reduce energy consumption.

reduce consumption 减少消耗

Saving water means cutting water consumption.

New words：

consume [kənˈsum] v.消耗；吃；毁灭；烧毁

详细词源拆解：

前缀 con- = 完全、彻底（加强语气）
词根 sumere = 拿、取、花费、占用（拉丁语）
词根变体：sum / sume

组合逻辑：

→ con- (彻底) + sume (拿取 / 用掉)
→ 全部拿光、用光 → 消耗；耗费；吃光；烧毁

词汇家族：

consume (v. 消耗) → consumption (n. 消耗) → consumer (n. 消费者)

必记高频搭配

consume energy / fuel 消耗能源 / 燃料

Cars consume a lot of fuel.

consume time 耗费时间

Watching TV may consume too much time.

be consumed by fire 被大火吞噬

The building was consumed by fire.