I (think) this room is (big) than that (one).改错!一上三处有错!

I (think) this room is (big) than that (one).改错!一上三处有错!
I (think) this room is (big) than that (one).改错!一上三处有错!

I (think) this room is (big) than that (one).改错!一上三处有错!
big改成bigger,只有一处错误,哪有三处错误的.不是钻牛角儿吗?