写一个有〖make one's mouth water〗这个词组的短对话.大概四到五个回合

mum:
Excuse me.Do you sell fruit here?
salesman：
Yes,we do.They're right in front of you.
Jack：The grapes look very good and they make my mouth water.
mum:yes,they loooks good.
jack:we can buy some.and it is cheap.
mum:all right.
mum;How much is it?
salesman：Final price…20 yuan