the house that they live is beautiful

1.应该是：the house that they live in is beautiful
因为 把句子正道过来 是 they live in the house 所以 in 不能少
2.应该是用词问题,把reached改为arrived更好（reach作为到达讲,是及物动词啊,后面必须接地点.不接的话是不及物动词,意思就变了,变为：延伸 与句意不符）
she arrived early so that she could sit in the front of the hall
她来得早,所以他能坐在礼堂的前面.

第一题that改为where，也可以在live后面加上一个in
第二题将reached改为arrived
不会的话欢迎追问，加油~~~

1.应该是：the house that they live in is beautiful