might have been can't be may be
must be can't have been must have been
The bird we saw in the park might have been a blackbird. They're common here.
1 Jane _____________ to at least 50 different countries by now – every year she travels for three or four months.
2 Andrew's plane landed in Málaga three hours ago. He _____________ at the beach now. I'm sure he's having a great time.
3 It's a public holiday tomorrow. There _____________ a lot of people at the airport.
4 The information in this guide book is all out-of-date. Its authors _____________ to Hungary for a long time!
5 This _____________ the only direct train to London. I'm sure there are more.
