late into the night还是long into...

‍▲late into the night 和 long into the night 都可以说，意思大致相同，均表示“深夜”，比如《牛津高阶英汉双解词典》(第四版)的 into 词条就有这样一句：

He carried on working long into the night. 他一直工作到深夜。

▲表示“深夜”，除long into the night外，还有以下相关表达：

1. deep into the night

They danced deep into the night. 他们跳舞直到深夜。

They sat and talked deep into the night.  他们坐着一直谈到深夜。

2. far into the night

He went on studying far into the night.  他继续学习至深夜。

My brother is really hard-working. He often works in his office far into the night. 我哥哥确实很勤勉。他经常在办公室里工作到深夜。(2008年高考英语天津卷)

3. late into the night

Security forces remained on patrol until late into the night.  保安部队继续巡逻至深夜。

If I can help it, I don’t like working late into the night. 如果我有办法的话，我可不喜欢工作到深夜。(2006年高考英语全国卷I)

4. well into the night

He works from dawn to dusk, and often well into the night.  他从早到晚地工作，经常工作到深夜。‍

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