1. Sue can't have/must have been at the party last night. She's on holiday in Italy right now. 2. Karen may/has to leave school early tomorrow. She has a dentist appointment after school. 3. If Mary gets permission from her parents, she may/must study in France next year. 4. Students mustn't/needn't run in the school corridors. It's against the rules.

1 - What are we doing on Tuesday? We are going to the cinema.
2 - Let's play football on Saturday. l am sorry, l can't. We are visiting our Grandma and Grandpa.
3 - Why don't you join us on the beach on Sunday morning? We are sorry, we can't. We are playing football in the evening. We are free on Sunday.
4 - Stuart, do you think Roy would like to visit a dog show on Thursday? l am afraid he can't. He is taking part in the running competition.
5 - Stuart, let's have a picnic on Monday evening. That's a good idea! Of course, l will.
      
       

1.
Simple Present: Do you  go on holiday by plane sometimes?
Present Progressive: Are you  going on holiday by plane sometimes?
2.
Simple Present: Do they play computer games every day?
Present Progressive: Are they playing computer games every day?
3.
Simple Present: Does she eat dinner at the moment?
Present Progressive: Is she eating dinner at the moment?
4.
Simple Present: What they do right now?
Present Progressive:What are they doing right now?
5.
Simple Present: Does she visit her grandma very often?
Present Progressive: Is she visiting her grandma very often?