“西气东输”是为了加强区域合作，实现优势互补。这体现了区域的开放性。

在研究“导体电流与电阻关系”的实验中，同学们利用了阻值分别为5Ω、10Ω、15Ω的定值电阻和变阻器进行了探究，变阻器规格是“10Ω 1A”，电源电压4.5V并保持不变．

    Ken is my friend. He ____ (come) from London, UK. Five years ago I ____(meet) him at Lily's party. Then we ____ (become) good friends. Ken and I ____ (reach) Washington D.C. at the same time. We____ (start) to study medicine in the same school. Now we are still studying together. So I know more about him. Ken is funny He often ____ (make) up some interesting stories to make me laugh. He says he's not going to be a doctor when he graduates (毕业). He ____ (want) to be an actor. He ____ (take) acting lessons when he is free. He ____ (make) lots of funny movies to make people happy. I believe his dream ____ (come) true.

①某景区风景宜人，游客们纷纷举起相机，留下最美的瞬间 
②十里不同风，百里不同俗，见到外国人最好离他们远点，避免发生不愉快 
③特产店购物时，先用手机扫一扫加微信公众号，查看产品的相关信息 
④就餐时，实行分餐制，吃多少，拿多少 
⑤在宾馆住宿，整夜开着灯和电视，反正钱已交了，不开白不开