假设复句 · HSK 4 (new at this level)

HSK 4 Pattern: 要是…否则/不然…

要是…就… introduces an if–then condition. A statement followed by 否则/不然 warns what happens otherwise. These are two frames, not a fixed 要是…否则 pair.

要是 + condition, (就)… ; 否则/不然 + bad consequence

Examples / 例句

要是明天不下雨，我们就去爬山。
Yàoshi míngtiān bú xià yǔ, wǒmen jiù qù páshān.
If it doesn't rain tomorrow, we'll go hiking.
要是…就 = simple if-then
你要早点出发，否则会迟到的。
Nǐ yào zǎo diǎn chūfā, fǒuzé huì chídào de.
You should leave early, otherwise you'll be late.
否则 = otherwise (formal warning)
快点写作业，不然来不及了。
Kuài diǎn xiě zuòyè, bùrán lái bù jí le.
Do your homework quickly, or you won't make it.
不然 = otherwise (casual)
你最好按时吃药，否则病可能会更严重。
Nǐ zuìhǎo ànshí chī yào, fǒuzé bìng kěnéng huì gèng yánzhòng.
You'd better take your medicine on time, otherwise your illness may become more serious.
最好 + 否则 + 可能会 = polite warning of a bad outcome — HSK 4 health context
我们得提前预订房间，不然到时候就没地方住了。
Wǒmen děi tíqián yùdìng fángjiān, bùrán dào shíhou jiù méi dìfang zhù le.
We have to book a room in advance, or there'll be no place to stay when we arrive.
不然 + 到时候 = casual contingency warning — HSK 4 travel-planning topic

Choose the meaning first / 先看要表达什么

要是没带伞，就先在这里等一会儿。This gives a plan under a condition. 带上伞，否则会淋湿。This warns about not following the advice. 否则/不然 points back to what came before; it can follow a full stop as well as a comma.

Practise the pattern / 开始练习 →

Common Errors & Meaning Differences / 易错点与表达区别

△ 要是你不来，否则我自己去。
✓ 要是你不来，我就自己去。/ 你最好来，否则我自己去了。
Don't combine 要是 directly with 否则 — 否则 already implies 'if not'. Either use 要是…就 or state the condition + 否则.
△ 否则努力学习，你不能通过考试。
✓ 如果不努力学习，你就不能通过考试。
否则 refers back to an earlier statement; it does not directly introduce 努力学习 as an if-clause. It may begin a new sentence when the previous sentence supplies the condition. 例如：请早点出发。否则，你会迟到。
Easily confused: 要是 A，就 B = if A, then B. Do A，否则/不然 B = do A, otherwise B. 否则 refers back to the preceding advice or condition. See comparison →

Fill in the Blanks / 填空练习

Fill every blank separately, using the meaning shown below the sentence. Spaces around words are ignored. Feedback lists reviewed answers; an unlisted rewrite is not automatically ungrammatical.

你得早点出发，会迟到的。

...otherwise you'll be late

明天天气好，我们就去爬山。

If the weather is good...

快点出发吧，来不及了。

...or we won't make it

Use it in a new sentence / 换句子表达

你建议朋友今天保存文件。如果不保存，关掉电脑后可能找不到刚才的内容。用“否则”或“不然”把建议和后果连起来。 / Save the file today, or the recent content may be lost.

否则指的是“不按前面的建议做”。 / Otherwise refers to not following the advice.

草稿只保留在当前页面，离开前请自行复制。Draft stays on this page only; copy it before leaving.

Compare one possible answer / 对照一种参考表达

你今天要把文件保存好，否则关掉电脑后可能找不到刚才的内容。

Other correct wording is possible. Check the intended meaning, not exact wording. / 可以有其他正确表达，重点是保留题意。

Quick Quiz / 小测验

你得多穿点衣服，___会感冒的。
Warning consequence → 否则 (otherwise you'll catch cold).
___你有时间，就来我家吃饭吧。
Simple if-then → 要是.
快走吧，___赶不上火车了。
Casual 'otherwise' → 不然.
All Grammar Topics Take a Mock Exam Sentence Ordering

要是…否则/不然… FAQ

When is 要是…否则/不然… tested in HSK 4?

要是…否则/不然… (If... otherwise...) appears in HSK 4 reading comprehension (Q66-85) when texts use complex sentences, in 阅读排序 (Q56-65) where this pattern's connectors signal sentence order, and in listening 段落 (Q26-45) where the speaker uses it to express presents a condition and warns about the negative consequence if it's not met.

What's the most common mistake with 要是…否则/不然…?

要是 A，就 B = if A, then B. Do A，否则/不然 B = do A, otherwise B. 否则 refers back to the preceding advice or condition.

Is 要是…否则/不然… required at HSK 4 or higher?

HSK 4 (new at this level)

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