Sigmoidal
反曲
🗣️ 情景例句
your doing this for Michelle and her friends.
你为 Michelle和她的朋友所做的这些。
He who purposes to be an author, should first be a student.
想当作家，相当学生。
You can enlarge your knowledge and learn some English at the same time.
你可以扩大你的知识面，同时又学习了英语。