Correct the mistake in the following sentences:
1) What has he________ all this time? We____________ for more than an hour. (do / wait). 2) I can’t understand what the writer __________________ (mean). 3) Oh, I _____________ my finger. It's bleeding. (cut). 4) Most teenagers ________________that they are wasting their time on the internet. (not / realize). 5) I always chat with her online, but in fact we ___________never___________ (meet)
