X 也就是说 / 也就是 Y
Reach for this when you want to restate or clarify what you just said in different words — 'that is to say,' 'in other words.' 也就是说 is the full form, used to introduce a paraphrase or implication of the previous sentence. 也就是 (without 说) is shorter and used to equate two phrases directly. Common in explanations, lectures, news commentary, anywhere precision matters.
Structure
[STATEMENT]，也就是说，[RESTATEMENT] / [X] 也就是 [Y]
yě jiù shì shuō... / yě jiù shì...
How to Think About It
也就是说 always points backward — the second clause re-expresses the first. The 说 ('say') flags 'in other words,' so it suits paraphrasing whole ideas. Drop 说 and you get 也就是, which links two equivalent labels directly: 他是CEO，也就是公司的最高领导. Use 也就是说 for ideas, 也就是 for things or names.
Examples
他是我爸爸的弟弟，也就是说，他是我叔叔。
Tā shì wǒ bàba de dìdi, yě jiù shì shuō, tā shì wǒ shūshu.
He's my dad's younger brother — that is, he's my uncle.
现在是九点，也就是说我们还有一个小时。
Xiànzài shì jiǔ diǎn, yě jiù shì shuō wǒmen hái yǒu yí ge xiǎoshí.
It's nine now — meaning we have one more hour.
这本书的作者是鲁迅，也就是中国最有名的作家之一。
Zhè běn shū de zuòzhě shì Lǔ Xùn, yě jiù shì Zhōngguó zuì yǒumíng de zuòjiā zhī yī.
This book's author is Lu Xun — that is, one of China's most famous writers.
Common Mistake
Learners use 也就是说 to add new information instead of restating. The pattern only works when the second clause is a paraphrase of the first — if it's a separate point, the listener gets confused.
他是CEO，也就是说他还有两个孩子。
他是CEO，也就是说他是公司的最高领导。
Don't Confuse With
就是说
Drop 也 and it becomes more direct, less concessive — same meaning, slightly more emphatic. Both work in speech.
换句话说
Literally 'in other words.' Same function as 也就是说 but slightly more deliberate. Use 也就是说 in flowing speech, 换句话说 when explicitly signaling a rephrase.
所以说
所以说 = 'therefore' (a conclusion). 也就是说 = 'in other words' (a restatement). Don't mix conclusions with restatements.
Practice
他周一出生，___ 一年的开始。
Show answer
也就是说
他是我妈妈的妈妈，也就是我的 ___。
Show answer
外婆
Arrange: 我们 / 也就是说 / 这次 / 失败了 / 考试 / 没有 / 通过
Show answer
这次考试我们没有通过，也就是说失败了。
She doesn't eat meat — in other words, she's a vegetarian.
Show answer
她不吃肉，也就是说她是素食主义者。
State a fact and then clarify what it means using 也就是说.
Show answer
我每天工作十二个小时，也就是说我几乎没有自己的时间。
Hear It in Real Episodes
This pattern appears in 4 Fluentide episodes:
也就是说：一个橘色的大球，忽然变成大球加几个红色的小球。
也就是说：一个大的橘色球，忽然变成了一个大的，加几个小的。
也就是说，你得了这种病，不会传给身边的人。