First, read the English article below.

The moon revolves around the Earth, and as it does, we see different angles of the moon’s illuminated surface. The moon doesn’t create its own light, but rather shines when it reflects the sun’s light.  As the moon transitions from new to full and back to new again, it goes through several phases, marked by its recognizable crescent and gibbous ("bulging") shapes, which are created by the moon’s own shadow. The moon phases are:  New moon Waxing crescent First quarter/Half-moon Waxing gibbous Full moon Waning Gibbous Third quarter/Half-moon Waning crescent New moon The moon travels the same path around the Earth every month, so it goes through the same monthly phases. The phases exist because from our perspective on Earth, we observe the illuminated portion of the moon differently as it makes its way around us. Remember that half the moon is always illuminated by the sun: it’s our vantage point on Earth that changes and determines what phase we see.  During the new moon, the moon is between the Earth and the sun, and is therefore not illuminated at all from our perspective. At this time, the moon’s illuminated side completely faces the sun, and we see the side that’s in full shadow. During the first quarter, we see half of the moon’s illuminated side and half of the moon’s shadowed side. The same is true in the third quarter, except the sides we see are reversed.  When the moon appears full, we see its full illuminated half, while the side that’s in complete shadow faces out into space. After the full moon, the moon continues its journey back to its original position between the Earth and the sun, which is another new moon. It takes the moon a little over 27.32 days to complete one full revolution around the Earth. However, a full lunar month (from new moon to new moon) is 29.5 days, because that’s how long it takes the moon to return to its position between the sun and Earth. On the moon’s journey from new moon to full moon, we see a growing portion of its illuminated half, and this is called the waxing phase... 

Now, please write a short abstract for it in Vietnamese. Abstract:
Học tên gọi các pha mặt trăng. Hiểu về ý nghĩa của các pha. Tìm hiểu nguyên nhân dẫn đến trăng khuyết đầu tháng và trăng khuyết cuối tháng.