Thanks for your help. I just found out 'late' is not right. However, Is 'My watch is off' American English? I heard it on TV show a lot. But I don't know if it means fast or slow? TN
In the US (the poster fivejedjon is British), "My watch is off." would be understood to mean your watch is either fast or slow.
If the correct time is 5 PM, and your watch shows 4:55 PM, then you'd say your watch is 5 minutes slow. If your watch shows 5:05 PM, then you'd say your watch is 5 minutes fast.