on the sky和in the sky的区别：中文含义不同、用法不同、强调重点不同。on the sky的含义为“画在天空”，强调“天空”这一整体概念；in the sky的含义为“在空中”、“中乃空”，是固定用法，表示在天空之中。

on the sky意为画在天空。

例句：So it looks the same angular size on the sky.

所以它们两个在空中看起来差不多大小。

Scribbling on the sky the message 'He is Dead'.

在天空狂草着信息他已逝去，

Silver jig heels on the purple sky rim?

紫色天穹镶边的银色高跟鞋？

The thought going on constantly in the night sky.

这种想法一直在夜空中回荡。

High on the sky so round and bright.

它在高高的天空上，又大又明亮。

And that's why he's always got his eyes on the sky.

这就是为什么他总是上了天空，他的眼睛。

We were on the sky wheel to feel the interesting, very fun.

我们还上了摩天轮上去体验了一回，很有趣。

Later, there is a rainbow on the sky.

尔后，天穹高挂虹彩。

in the sky意为在空中;在天空中;中乃空。

例句：Thunder boomed in the sky overhead.

雷声在天空中隆隆作响。

Several people described seeing strange lights in the sky.

好几个人都说看到天上出现了奇异光芒。

The dark clouds in the sky meant that a storm was coming.

天空中的乌云预示暴风雨即将来临。

It was late afternoon and the sun was low in the sky

当时是傍晚时分，太阳低悬于空中。

He can't help thinking it's all just 'pie in the sky' talk.

他禁不住想所有这些不过是“画饼充饥”的空话而已。

Mars is too faint and too low in the sky to be observable.

火星星光暗淡，位置低悬，难以看见。

Huge balloons bobbed about in the sky above

一个个巨大的气球在头顶的蓝天中漂浮着。