The following video demonstrates each syllable of the pinyin structure
and the exercise of pinyin/zhuyin with basic Chinese 4-tune pronunciation

Mandarin pinyin tunes
Click the framed calligraphic Chinese symbol icons
to link more related multi-character Chinese words!

rēn, rén, rěn, rèn

second tune

rén

human being people; person 人 rén

humanity; mercifulness kindness; kindhearted 仁 rén

Chinese characters also pronunced rén

third tune

rěn

endure; tolerate 忍 rěn

ninjia 忍者 rěn zhě
endure 忍 rěn	person 者 zhě

Chinese characters also pronunced rěn

fourth tune

rèn

blade of a knife cutting edge of a knife 刃 rèn

allow; let be 任 rèn

recognize admit; acknowledge 認 rèn

know; recognize; familiar with 認識 rèn shì
recognize 認 rèn	know 識 shì

Chinese characters also pronunced rèn