The factory was built in a secret place,around which were high mountains.为什么是which were?

was ,buil,the,first,computer,1946,in(连词组句) sad,bewas ,buil,the,first,computer,1946,in(连词组句)sad,be,feels,after,exams(连词组句) The first factory was built in _____ this is the factory.his father used to work this is the city...Ithis is the factory.his father used to workthis is the city...I have been expecting to visitshe is looking for her bike...she lost yesterdaya new school building will be buil .there used The factory was correcting this problem (yesterday)说法对吗? he was very busy in the factory .he was very hungry when he got home. The man was in that shoe factory(工厂)——— ,but now he works in a car factory. The factory which/that was built in 1978 has closed.该为：The factory was built in 1978 has closed.是改为 The factory was built in 1978 has closed. There was a factory near the hospital in the past 同义句 The river ________ (become) dirty since the paper factory was opened up. before the ___(close) of the factory ,noise pollution was always a serious problem. The reason that the factory was burned down has not been found out. The factory ( )I visit yesterday was not the one( )I once worked. Was water pollution a problem before the (c )of the factory. It was the factory that he used to work that was shut down the other day改错 英语翻译You're not met by imposing doors and concrete walls ,and the buildings were inviting（吸引人的）.On the front of the main building was inscribed Lee Elementary School,1904. Wow!I knew it was an old school.Surrounding the main buil There was a shoe factory in the past.的同义句 Mr Wang ____ （work）at the factory since he was young. The factory ----- Mr Li used to work was closed last week.填where 还是which ..理由