C= Customer S= Salesperson
C: Excuse me, I'd like to have these pants I bought here yesterday altered. Here's my receipt.
S: Certainly, sir. What would you like done to them?
C: They're a little bit too long, so I'd like about half an inch taken off them.
S: All right, sir. They should be ready for you by tomorrow afternoon.
C: Thank you very much.
S: It's our pleasure.
a pair of pants 一条裤子
a pair of scissors/trousers/glasses
例：A publisher can't alter a book without the author's permission.
4．take sth off 把某物拿掉
例：John took the bumper stickers off his car.