1. sky
2. heaven
3. sphere
4. welkin
5. firmament
6. empyrean
7. heavens
8. skies
9. cloud
10.air
Examples:
1. 她擡起頭來，凝望著十二月份陰沈沈的天空。
She looked up staring at the sombre December sky.
2. 雲是天空中的水汽團。
A cloud is a mass of vapor in the sky.
3. 暴風雨來臨時，天空轉暗。
The sky turned dark as the storm came near.
4. 天空慢慢由藍色變為紅色。
The sky slowly changed from blue to red.
5. 落日把天空染成金色。
The setting sun gilds the sky.
6. 他擡起頭，凝望著天空。
He rose his head and stared at the firmament.
7. 清澈的水中映出蔚藍的天空。
The clear water mirrored the blue sky.
8. 太陽看起來在天空以弧線運行。
The sun appears to move in an arc across the sky.
sky brightness
天空亮度
A dull sky.
陰沈的天空
River Phoenix
不羈的天空
The sky; the firmament.
天空；空間
The sky cleared.
天空放晴了
It looks blue.
天空是蔚藍色。
Of the sky; celestial.
天空的；蒼天的
The sky is blue.
天空是蔚藍色的。
The sky is deep blue.
天空是深藍色的。
The sky was deep blue.
天空是深藍的。