意思是：到达并在…登记；调查；
句子实例：
Bob began to go into the details of the question.
鲍勃开始深入调查这问题的细节。
Related departments are going deep into this affair.
有关部门正在深入调查这事件。
She has just checked into the hotel.
她刚刚在旅馆办好住宿登记。
I hope to check in for the next flight.
我希望登记乘下一班飞机。
