19.Dear Sam, You asked me to go climbing this Saturday. (1)謝謝你邀請我。 I really want to go with you,but I'm sorry to say that I can't go.I'm busy and I don't have time to take a good rest that day.In the morning,I have to get up early to meet my cousin at the airport (機場).She is flying here to see my grandma.You know (2)my house is far from the airport,so it will probably take me the whole morning to meet her,and then (3)we will take the bus to my grandma's house.And(4)I have to prepare for the exams in the afternoon.There is another thing.My dog Atom is ill.I have to take it to see a doctor.I hope I can go with you next time.(5)祝你玩得愉快! Yours, Jenny (1)