At night,the moon is high in the sky__a light.为什么不填looks like我觉得looks like 应该改为looking like .是不是因为It looks like a light.而不是It looked like a light.所以就应该改成looking like而不是looked like?然后请简析句子语法结构好让我更清楚为什么不能用looks like第二行修改一下：是不是因为It looks like a light.而不是It is looked like a light.所以就应该改成looking like而不是looked like?

这是非谓语，前面的is是谓语，所以后面的look是非谓语，非谓语的选择要看主被动关系，如果，这里如果写looks like，那么它就也是谓语，句子成分怎么算？所以不用s,如果要写，就看主被动关系。

At night是状语,
the moon 是主语
is是系动词
high in the sky是表语
looking like a light是现在分词短语 作伴随状语.
不是因为 你说的原因 因为这是简单句 如果用 It looks like a light.前面必须是句号 或者 加and
At night,the moon is high in the sky looking like a light.
=At night,the moon is high in the sky and looks like a light.
=At night,the moon is high in the sky .it looks like a light.
另外 look这里 是系动词 是没有被动语态的