Mandy: Hi, have any of you paid the electricilty bill?
Sarah: I don't know
Josh: what's the date on the bill?
Mandy: 24th
Josh: I haven't
Josh: I was sure Sarah did
Mandy: she didn't, apparently
Mandy: there's a demand for payment
Sarah: that's strange 
Sarah: I paid one a few days ago...
Josh: dear lord...
Josh: are you sure?
Sarah: wait... let me check my account
Sarah: yeah. I paid 20 pounds 2 days ago
Mandy: that was a different bill, because this one is for 37
Sarah: oh
Mandy: Okay, I'll pay it
Mandy: But you will have to pay me back as soon as you're back
Josh: thanks, Mandy
Mandy: incl. interest ;)
Sarah paid an electricity bill of 20 pounds two days ago. There is a new bill for 37 pounds Mandy will pay. She want Josh to pay her back.