instance

1. like ^{频率：★★★★★（日常和口语最常见）}

用法：用于比喻、举例，后面接名词/代词/短语。特点：口语非常常用，非正式；注意不要和 as 混淆。

• He runs like a cheetah. ^{（他跑得像猎豹一样快。）}
• Some fruits, like apples and bananas, are high in fiber. ^{（一些水果，比如苹果和香蕉，富含纤维。）}

2. such as ^{频率：★★★★★（书面语、正式）}

用法：举例说明，常用在句中，后面接具体例子。特点：比 like 更正式，更适合书面语、学术语境。

• Many animals, such as lions and tigers, live in the savanna.
• We should eat more vegetables, such as spinach and broccoli.

3. for example ^{频率：★★★★☆}

用法：举例时常放在句首或句中，后接完整句子或名词。特点：常用于正式、半正式语境，写作中很常见。

• For example, you can try jogging in the morning.
• Some countries, for example Canada, have universal healthcare.

4. for instance ^{频率：★★★★（稍低于 for example）}

用法：和 for example 基本同义，但语气略正式。

• You should eat more vegetables; for instance, carrots and beans.
• Some sports, for instance football, are extremely popular worldwide.

5. as ^{频率：★★★★}

用法：表示比喻或“作为…”，用在正式或半正式语境。特点：比 like 更书面；表达身份或角色时多用 as。

• He acted as a guide during the trip. ^{（作为导游）}
• Do it as I showed you. ^{（按照我展示的方式做）}

 6. such…as ^{频率：★★★☆}

用法：用于强调某类事物中的例子。

• I don’t trust people such as him.
• Problems such as poverty and pollution are hard to solve.

7. namely ^{频率：★★★（多见于正式/学术/法律语境）}

用法：用于“即，也就是”，常用于明确举例。

• Three students were absent, namely Tom, Jack, and Lucy.
• There’s only one possible reason, namely, that he forgot.

8. to illustrate  ^{频率：★★★}

用法：引导举例，常用于学术写作或演讲。

• To illustrate, let’s look at the case of water pollution.
• Some animals migrate thousands of miles; to illustrate, consider the monarch butterfly.

9. say ^{频率：★★☆（口语里举例）}

用法：非正式，举个例子时说 “say”。

• You could try, say, going for a walk after dinner.
• Let’s assume, say, 10% of the population agrees.

10. in other words ^{频率：★★☆}

用法：用于换一种方式说明，带有解释性质。

• He is an introvert. In other words, he prefers being alone.
• The plan failed; in other words, we need to start over.