更糟糕的是北京收紧了大陆居民出境旅游的签证六月份由每月两次调整为每月一次，最近更调整为两个月一次。

Worse still has been Beijing's tightening of the availability of travel visas for mainland residents, from twice a month to once a month in June and, more recently, to once every other month.

youdao

So this design of having students on campus once a month for intensive classes allows students to continue working full time.

让学生每月来校一次,进行现场教学的设计,允许学生继续全职工作。

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