Are these sentence correct?

Mobile phone which was stealed yesterday is whose?
昨天偷走了的手机是谁的?
How can find a cheap renthouse?
怎么能找着便宜房租的房子?
Would you please take off your hat?
请你摘下你的帽子可以吗?
If you want to improve, what should you do?
如果你想提高,你 要做什么?
Have you ever climb a long path on mountain?
你以前长途爬山过吗?
Have you ever had a hard goodbye?
你以前有过一段艰难告别吗?
Who was called by broadcast?
广播里在点名谁 ?
You decided how to go from Tehran to Mashhad ?
从Tehran到Mashhad你选择怎么走?
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?
看看火车窗外你看到了什么?