al·ter·nate an·gles
noun/ɔːlˌtɜːnət ˈæŋɡlz/
/ˌɔːltərnət ˈæŋɡlz/
[plural] (geometry)- equal angles formed on opposite sides of a line that crosses two parallel lines, in the position of the inner angles of a Z
enlarge image（内）错角