Are these sentence correct?

Mobile phone which was stealed yesterday is whose?
昨天被偷走了手机是谁的?
How can find a cheap renthouse?
怎么能找着便宜的出租房?
Would you please take off your hat?
可以请你摘下你的帽子吗?
If you want to improve, what should you do?
如果你想要提高,你应该 要做什么?
Have you ever climb a long path on mountain?
你以前在山上爬过这么长的路吗?
Have you ever had a hard goodbye?
你以前有过不舍的告别吗?
Who was called by broadcast?
广播里谁被点名?
You decided how to go from Tehran to Mashhad ?
从Tehran到Mashhad你选择怎么去？
After the train started to move what can you do?
火车开了以后你可以做什么?
Looking outside window in train, what did you see?
看看火车的窗外，你看到了什么?