Welcome back for those returning, welcome to CS50 for those joining us for the first time.

欢迎老同学，也欢迎新同学。

哈佛公开课 - 计算机科学课程节选

For those of you who are new to the class,welcome A couple of administrative things.

新加入的同学们，欢迎,一些行政上的事情。

麻省理工公开课 - 固态化学导论课程节选