KANJI GUIDE
The sky, and heaven with it. 天国 is paradise; 天気 is the weather.
Half of 瑠璃, the deep blue stone. On its own it is used mostly for its sound and its colour.
A leaf. 言葉, the word for language, is literally leaves of speech.
The sky, and also empty. Buddhism uses the same character for emptiness — 空, śūnyatā.
The capital, and any big city. 東京都 is the Tokyo Metropolis; 都合 is how your circumstances stand.