Complete the 12 sentences below. Choose the best answer for each one.
1Lena ............... at home; she has just posted a photo from the airport check-in desk.
Wrong!
Use "can't be" because the visible evidence says Lena has just checked in from the airport, so being at home now is impossible.
2The nurse ............... exhausted after working a double shift without a proper break.
Wrong!
Use "must be" because a double shift is strong evidence for a confident present deduction.
3The lights are off, but I haven't looked at the opening hours, so the shop ............... closed.
Wrong!
Use "could be" because the speaker has no clear evidence, so the shop being closed is only a possibility.
4The live map shows the taxi outside our building, so the driver ............... waiting for us.
Wrong!
Use "must be" because the live map gives strong present evidence that the driver is already outside.
5That ............... the manager; the person in the photo looks about twenty, and the manager is retiring next month.
Wrong!
Use "can't be" because the person in the photo is visibly too young to be the manager described as retiring next month.
6Tom ............... have a key, because he got into the office while the alarm was still set.
Wrong!
Use "must" because entering while the alarm was set is strong evidence that Tom has a key now.
7Her headphones are unplugged on the desk, so she ............... listening to the call through them.
Wrong!
Use "can't be" because if her headphones are unplugged on the desk, she is not listening through them now.
8His reply was only two words, so he ............... angry, but he could also just be busy.
Wrong!
Use "might be" because a short reply is a possible sign of anger, but it is not enough for certainty.
9Mira's calendar says her presentation runs from 3:00 to 4:00, so she ............... be free at 3:15.
Wrong!
Use "can't" because being in a presentation at 3:00 makes being free at 3:15 impossible.
10The director has called three times during the meeting, so the message ............... important.
Wrong!
Use "must be" because repeated calls from the director during a meeting are strong evidence that the message is important.
11This file is labelled draft 1, so it ............... be the final version.
Wrong!
Use "can't" because a file labelled draft 1 cannot be the final version.
12Sara has raised her hand, so she ............... know the answer, although she may just want to ask a question.
Wrong!
Use "might" because raising her hand suggests possible knowledge, but it is not certain.
Done.
Score: 0/12
Answers
- Lena can’t be at home; she has just posted a photo from the airport check-in desk.
- The nurse must be exhausted after working a double shift without a proper break.
- The lights are off, but I haven’t looked at the opening hours, so the shop could be closed.
- The live map shows the taxi outside our building, so the driver must be waiting for us.
- That can’t be the manager; the person in the photo looks about twenty, and the manager is retiring next month.
- Tom must have a key, because he got into the office while the alarm was still set.
- Her headphones are unplugged on the desk, so she can’t be listening to the call through them.
- His reply was only two words, so he might be angry, but he could also just be busy.
- Mira’s calendar says her presentation runs from 3:00 to 4:00, so she can’t be free at 3:15.
- The director has called three times during the meeting, so the message must be important.
- This file is labelled draft 1, so it can’t be the final version.
- Sara has raised her hand, so she might know the answer, although she may just want to ask a question.

