But how can they cancel the class after offering it?

但是他们怎么能在提供课程后取消它呢？

youdao

You avoid the travel to and from class, and on the Internet it is easy to cancel or change your tutor whenever you want.

你可以免受来回上课的劳顿，在互联网上，随时撤换家庭教师是很容易的事。

youdao

The TimerTask class has a cancel method that you can use to cancel subsequent invocations of the task.

timertask类有一个cancel方法，可以用它取消对任务的后续调用。

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"Several students were crying and begged me to cancel class, " he said.

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The proposed plan would retire seven cruisers early, delay construction of the next large-deck amphibious warfare ship by one year, cancel the second Virginia-class nuclear-powered attack submarine (SSN) in 2014, delay construction of two smaller amphibious warfare ships, and reduce procurement of littoral combat ships by two and joint high speed vessels by eight.

CENTERFORSECURITYPOLICY: Section IV: Building a Two-MRC Force for the 21st Century

Summer Smith Hull, who blogs about frequent-flier miles for families, checks over and over for seat assignments if she doesn't get them right away, grabbing seats that open up when travelers cancel or get upgraded to first class.

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