You’ve seen how to use 回 to say sentences like 今天晚上我不回家 . 回 can also mean to return a call or to reply to an email.
他会马上回你的电话。
Tā huì mǎshàng huí nǐ de diànhuà.
He will immediately return your call.
我还没有回你的电子邮件。
Wǒ hái méiyǒu huí nǐ de diànzǐ yóujiàn.
I still have not replied to your email.
你为什么不回我的短信？
Nǐ wèishéme bù huí wǒ de duǎnxìn?
Why didn’t you reply to my text message?
Here’s another example of a character that changes tone based on the word it’s in.
| 发 | 头发 tóufa hair 发现 fāxiàn realize 发短信 fā duǎnxìn send (a message) |