send in
phrasal verbsend somebody  in 
- to order somebody to go to a place to deal with a difficult situation派某人去(应付困难局面) - Troops were sent in to restore order.部队被派去恢复秩序。 
 
- Troops were sent in to restore order.
send something  in 
- to send something by post to a place where it will be dealt with寄去(处理) - Have you sent in your application yet?你把申请书寄去了没有? 
 
- Have you sent in your application yet?