1）My hotel room overlooked a courtyard.There was a fountain.There were several trees.(in which...and)
答：My hotel room overlooked a courtyard in which a fountain and a several trees.(需要改为：in which there was a .in which=where)
2）Uncle Li looked everywhere for his glasses.He could not find them.(Though)
答：Though Uncle Li looked everywhere for his glasses could not find them.(改为.his glasses,he could not ...,如果改为Uncle Li could not find his glasses,though he looked everywhere for them.会更通顺.)
3) During Christmas,there was extra work at the office.A great number of students were employed to help.(so much...that)
答：There was so much extra work at the office that a great number of students were employed to help during Christmas.
OK!
4)I don't want to see that film.It had poor reviews.(because)
答：I don't want to see that film because it had poor reviews.
OK!
5)Wages shave gone up.Prices will rise.The cost of living will be highter than ever.(Now that...and)
答：Now that the cost of living will be highter than ever wages have gone up and Prices will rise.
改为：Now that Wages have gone up,prices will rise and the cost of living will be higher than ever.