Some people can study with lots of activities going on and others need absolute quiet.
一些人可以在学习的同时做其它很多事情，其他人需要绝对的安静。
This meant that many different activities were going on at the same time.
也就是说，很多不同的活动是同时进行的。
Check whether all activities are going on schedule.
检查所有活动是否已经按计划进行。
Check whether all activities are going on schedule.
检查所有活动是否已经按计划进行。
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