Students who return to the dormitory late for whatever reason must register upon entering with proper identification.

因特殊原因不能及时回宿舍者，凭证件登记后方能进入。

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According to the U.K. border agency, it takes between five to 10 minutes to register for IRIS and a registered traveler entering the U.K. by passing through the IRIS barrier can clear immigration in about 20 seconds.

WSJ: Cutting Down On the To and Fro