Chinese Tone Pairs

 This is about Chinese tones. Either you know what it means and care or don't and shouldn't.

Tone duration: 4th is shortest 3d is longest.

4123

Tone pairs: classical Chinese was monosyllabic and in its earliest days a-tonal. Contemporary Chinese is mostly bisyllabic and tonal. Tones should be learned in pairs. Admissible tone pairs in Chinese:
12
13
14
21
23
24
31
32
34
42
43
44

I am still hoping to find a frequency table arranged by tones either for phonemes or characters.

The following are impermissible tone combinations.

11
22
33
41