the house is built on soft land is easy to fall down.这句话哪里错了

first man to land on moon is an America.哪里错了, The old house is built ( ) stone He is standing on the top of the hill.这句话哪里错了? is so easy to fall in It is time to get down to do some serious work 这句话哪里错 The house 什么 is being built is near the factory. the boy is old enough to go to school.这句话哪里错了? next to our house is the library 这句话对吗 还是Our house is next t He is to clean the house这句话对吗 This house is easy to keep clean. The house being built over there is to be completed next mon To pass the test ,more hard work is needed 这句话哪里错了