This is a tough one. When we see the full moon, we know that the sun is on the opposite side of the sky, 180 degrees away. Venus, however, is never seen far from the sun. The orbit of Venus is inside the orbit of earth, so it could never appear anywhere near 180 degrees away from the sun. Although you may often see Venus near a crescent moon, you won’t see Venus near a full moon.

This diagram shows the relative positions of the Sun, Venus, Earth, and the full moon. Notice that the full moon is on the opposite side of Earth from Venus.