Optional argument
[计] 任选变元
🧩 词语组成解析
🗣️ 情景例句
When you understand the cultural background, you can better use the language.
当你了解了文化背景，你就能更好地运用语言。
I am afraid I will not be able to accompany you.
我恐怕无法跟你在一起了。
Look at those people in the boats.
瞧船里的那些人！