那就好 is a colloquial expression that means "That's good" or "That's fine" in Chinese. It is used to express approval or acceptance of something.

The expression likely comes from the phrase 那就 (nà jiù), which means "in that case" or "if that's the case." It is often used to indicate agreement or acceptance of a previous statement or suggestion.

Here are some examples of how you might use 那就好 in a sentence:

A: "你今天有空吗？" (Nǐ jīntiān yǒu kòng ma?) "Are you free today?"

B: "那就好，我们可以一起出去玩。" (Nà jiù hǎo, wǒmen kěyǐ yīqǐ chūqù wán.) "That's good, we can go out and play together."

A: "我想吃炸鸡。" (Wǒ xiǎng chī zhá jī.) "I want to eat fried chicken."

B: "那就好，我们去那家炸鸡店吧。" (Nà jiù hǎo, wǒmen qù nà jiā zhá jī diàn ba.) "That's good, let's go to that fried chicken restaurant."