Let's go out for lunch.

咱们出去吃午饭吧。

《牛津词典》

Why don't we close up and go out for lunch?

我们为什么不关上门出去吃顿午饭？

《牛津词典》

Okay, well, I'm out all day today, but I should be in tomorrow morning before I go out for lunch.

好吧，我今天一整天都在外面，但是明天上午，午饭之前我应该在。

youdao

I think I'm going to go out for lunch.

我就要去吃午餐了。

I'm about to 实战 - SpeakingMax英语口语达人

I'm about to go out for lunch.

我就要去吃午餐了。

I'm about to 实战 - SpeakingMax英语口语达人

The question remains - will they bother, or will they go out for lunch instead?

BBC: 'Free banking': Good thing or barrier to competition?

"Being able to go out for lunch with the best view in the city was a big selling point, " Mr. Guttmann said.

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We'd go out for lunch and have a great gossip together.

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