题干
假如你是李华，你的好友李娜要邀你一起去西藏旅行，但你得陪同父母去看望在乡下的爷爷奶奶，所以不能去。请以电子邮件的形式给你的朋友提一下旅行建议。
1）加入旅行社，同时结伴而行；
2）早晚气温较低，带上轻薄的棉衣;
3）日照时间长，带上太阳镜，遮阳帽等物品；
4）空气稀薄，戴上吸氧用具。
(西藏Tibet 旅行社 travel agency 吸氧用具 Oxygen inhalation apparatus)
答案(点此获取答案解析）
Dear Li Na,
I feel sorry that I can't go to travel to Tibet with you. In the holiday of May First, I need to go with my parents to visit my grandparents who live in the countryside.
As your best friend, I'd like to give you some advice ab
