Classroom language

Sorry, that was my fault.

• Sorry, that was my fault.
• Excuse me.
• Sorry, I am a little bit late. I was delayed by the traffic.
• Sorry I am late. I give my apologies to everyone here.
• I’m terribly sorry.

Late-comers

• Where have you been?
• We started ten minutes ago. What have you been doing?
• Did you miss your bus?
• Did you oversleep? Don’t let it happen again.
• What do you say when you are late?
• What's your excuse? Your alarm-clock didn't go off?
• Did you oversleep? Try not to be late next time.
• That's all right. Sit down and we can start. 
• This is the third time you've been late this week

An apple a day keeps the doctor away!

• How is X getting on? Is she any better? Has her temperature come down? Why did you miss last Monday lesson? Where have you been for the last few days? How are you feeling today?
• I think you'd better go to the sick-room. I hope you've recovered from your cold? Have you got a doctor's note/medical certificate? Do you have a good reason for having missed my class?