假如你是李雷, 你的笔友 David 计划来北京旅游, 他非常想知道北京的天气情况. 请给他写一封回信介绍一下北京的天气, 并欢迎他来北京旅游.
要求: 包括以下信息, 语句通顺, 50词左右.
    1. 夏热冬冷, 颐和园 ( the Summer Palace) 非常美丽;
    2. 秋天( autumn) 凉爽, 香山红叶 (red autumnal leaves in Xiangshan Mountain) 非常美丽.
                                                                                                                                              
                                                                                                                                              

1. 刚才他奶奶怎么啦？
    _____________________________ his grandmother just now?
2. 北京的天气与广州的天气大不一样。 
    The weather in Beijing _____________________________ in Guangzhou.
3. 昨天你看见一位老人走进了那家商店了吗？
    Did you _____________________________ yesterday?
4. 两年前他痴迷于和网友聊天，是吗？ 
    He _____________________________ on the Internet two years ago, wasn't he?
5. 叫那两个孩子小心烟火。
    Tell the two children _____________________________ fire.
6. 再也不要作弄那个男孩了，好吗？
    _____________________________ the boy _____________________________, will you?