It may not be so wise for me to explain my points with Coriolis Force. So I reexplain my point with other ways.
Take the second image for example.


Let’s see what will happen if the moon circles the earth freely around the earth polar orbit counterclockwise.

When the moon is right over the earth's north pole, its relative velocity (V) to the sun is the same as the earth because they are at the same orbit distance to the sun. Now the moon circles in, its centripetal force (F) to the sun is reduced. Why, because part of it is balanced off by the earth on the opposite side. On the other hand, its distance to the sun (R) is shortened now. Now let's use the formula



The F and the R are both reduced, but its velocity keeps the same as the earth. So once the moon moves in between the Sun and the Earth, the moon will have redundant velocity and will go faster than the F and R need it. The moon will go ahead of the earth.

Track man knows this principle well in the track and field running game. The first running athlete always occupies the most inner track while turning rounds to prevent others go ahead of him.

Now the moon is in the inner track and with the same relative velocity to the sun, it will surpass the earth. Thus moon’s orbit changes.

When the moon is ahead of the earth, universal gravitation force of the moon-earth and the moon-sun will apply a resultant force that will slow down the moon, only when the speed of the moon is adjusted down by this can the V, F and R in the above formula be kept balanced.