Lunar phases depend on the positions of the Earth, Moon, and Sun. The Moon rotate once each month. This keeps the same face towards the Earth. Moon passes between the Earth and the Sun Moon's shadow cast on the Earth. In an annular eclipse, the umbra doesn't reach the Earth.
Earth passes between the Sun and the Moon Earth cast's a shadow on the Moon.
Earth's umbra can completely cover the Moon. Red light bent by the Earth's atmosphere still reaches the Moon. They also move with respect to the stars. Mars, Jupiter, Saturn, can be up to 180 o from the Sun.