were后动词是否要用ing:是they were have还是having?

were后动词是否要用ing:是they were have还是having?
were后动词是否要用ing:是they were have还是having?

were后动词是否要用ing:是they were have还是having?
应该是 they were having
例如：They were having supper when I called them.当我打电话给他们的时候,他们正在吃饭.
be doing sth,
were 是 are 的过去时,属于be动词