"know from memory" in Chinese (Simplified)
背下来记住（不看资料）
Definition
在不用参考资料的情况下准确地记得或复述，因为你已经背下来了。
Usage Notes (Chinese (Simplified))
适度正式，用于数字、诗歌、列表等。比“记住”更突出已经掌握的状态。常与“背下来”一起用，也可表达“背诵”。
Examples
I know from memory all my friends' birthdays.
我**背下来**了所有朋友的生日。
She can know from memory hundreds of phone numbers.
她可以**背下来**上百个电话号码。
Do you know from memory the national anthem?
你**背下来**国歌了吗？
He rattled off the list as if he knew from memory every name.
他像是把每个名字都**背下来了**似的，一口气念出了名单。
After practicing, I could know from memory my part in the play without any mistakes.
练习之后，我能完全**背下来**自己在剧中的台词，毫无差错。
If you really know from memory these facts, you won't need your notes during the test.
如果你真的**背下来**这些内容，考试时就不需要看笔记了。