sign in：签到
check in：打卡



拓展资料
打卡上班：punch in，clock in/clock on(UK)
举个例子
1. 我们早上九点打卡上班。
We punch in at 9 a.m.
2.今天早上你什么时候打卡签到的？
What time did you clock in this morning?
打卡下班：punch out，clock out/clock off(UK)
举个例子
1.你昨晚走的时候怎么不打卡？ 
Why didn't you punch out when you left last night?
2. 他昨天提早打卡下班离开了。
He clocked out early yesterday.