We can consult an almanac, the Internet, or our handy full moon calendar, of course. But if you learn the moon phases, you can wager a pretty good guess no matter where we are in the lunar cycle just by observing the moon and doing the math. ...
1英文Draw a diagram showing the Sun and the orbits of Venus,Earth and Mars.a.Use your model to explain why Venus is visible only in the morning or evening sky,but Mars can also be seen at midnight.b.Venus goes through phases,like the moon.On your diagram,show where Venus would be wh...
翻译部分：画出太阳以及金星、地球和火星的运行图,然后：a,用你画的图解释为什么金星只能在黎明和黄昏时...