Why not( )(stop)them from( )(do)

Why not( )(stop)them from( )(do)
Why not( )(stop)them from( )(do)

Why not( )(stop)them from( )(do)
Why not( stop)(stop)them from(doing )(do)
why not do sth
stop sb from doing sth 阻止某人做某事
希望能够帮到楼主

Why not stop them form doing