[解析]
M:Hello.Can I help you?
W:I hope so.I was sitting in that restaurant over there and when I had finished my meal,I forgot to pick up my backpack.Has anyone handed it in as lost property?
M:What does it look like?
W:It's quite small,and It's made of plastic.It's not leather or anything.
M:Has it got a pattern on it?
W:No,it's gray with a handkerchief tied to it.
M:Well.You're in luck.This one was handed in by the restaurant staff 10 minutes ago.