The stars we see at night are really huge like our sun, but they are much farther away in space. Some of them have planets(行星)like our earth travelling around them.
The stars are so hot that they give off great light and heat--more than the hottest, brightest fire you can imagine(想象). As we all know, light travels at the speed of 300, 000 kilometres per second. But the stars are so far away that their lights still take years to reach us. The light we see coming from some far-off stars started for the earth more than a hundred years ago.
The moon is a ball of cold rock. It is smaller than the earth. It circles round(环绕)the earth as the earth circles round the sun. The whole journey(旅程)of the moon round the earth takes twenty-eight days. We see it changing from new moon to half to full and back to new moon every twenty-eight days. Our word "month" comes from the word "moon".
1.The stars we see at night are very small.2.The earth travel around the planets.
3.It takes years for the light to reach the earth because the stars are so far away
4.The word "month" comes from the word "moon".
5.There are twenty-eight days in a month.
6.The moon turns around the earth but not round the sun.
同类型试题
y = sin x, x∈R, y∈[–1,1],周期为2π,函数图像以 x = (π/2) + kπ 为对称轴
y = arcsin x, x∈[–1,1], y∈[–π/2,π/2]
sin x = 0 ←→ arcsin x = 0
sin x = 1/2 ←→ arcsin x = π/6
sin x = √2/2 ←→ arcsin x = π/4
sin x = 1 ←→ arcsin x = π/2
y = sin x, x∈R, y∈[–1,1],周期为2π,函数图像以 x = (π/2) + kπ 为对称轴
y = arcsin x, x∈[–1,1], y∈[–π/2,π/2]
sin x = 0 ←→ arcsin x = 0
sin x = 1/2 ←→ arcsin x = π/6
sin x = √2/2 ←→ arcsin x = π/4
sin x = 1 ←→ arcsin x = π/2