How would the apparent diurnal motion of the Moon occur if its sidereal month was exactly equal to sidereal days?

How would the apparent diurnal motion of the Moon occur if its sidereal month was exactly equal to sidereal days? How would it happen if the sidereal month was less than a sidereal day, for example, equal to 20 hours?

At every point on the Earth, the Moon would occupy an unchanging position behind the horizon and on one hemisphere of the Earth would be forever invisible. In the second case, the Moon would rise in the west and set in the east.