They often helped each other when they were at school.把这句话改成否定句和疑_英语解答

They often helped each other when they were at school.把这句话改成否定句和疑问句.
急

人气：240 ℃　时间：2020-05-08 11:00:41

解答

They didn't often help each other when they were at school.
Did they help each other when they were at school?