第一人称随主语变,第二人称随宾语变,第三人称不变,即一随主,二随宾,三不变.
He said "My brother wants to go with me." He said his brother wanted to go with him.
He said to Mary "How is your mother now?" He asked Mary how her mother was then.
Mr Li said "Tom is a good student." Mr Li said Tom was a good student.