Sourceless
a. source的变形
🗣️ 情景例句
I'm extremely sorry for the delay.
对此延误，我深感抱歉。
He learns Japanese every day.
他每天都学日语。
We must thank Mr. Hu. He kept asking us to remember TEAMWORK.
我们得感谢胡老师。他反复告诫我们记住配合。