人 - 入 - 八

入 means "to enter", "to go into". Its pictogram resembles an arrowhead. In print, to distinguish 人 from 入 pay attention to the hook at top left. 

人 means "a man". Therefore, its pictogram resembles human's legs. Though in print, the modern form of the character 人 has symmetric legs, its ancient version depicted a man with arms and asymmetric legs. 

- How to distinguish 人 from 入 in handwriting?
- In 人 the right leg is shorter； in 入 the right leg is longer. 

八 is composed of two strokes: 丿 and 乁. These two bent lines are believed to signal "division". Of all single-digit numbers, 8 can be divided by 2 the greatest number of times. 

人, 入, 八 As Radicals

All these characters are radicals. In dictionaries, the most commonly used characters, found under 入 radical, are 內 and 全. The radical 人 is often simplified to 亻. It exists in many characters: 什, 仃, 㐰, 仔, 㐸, etc. 

八 is frequently simplified to 丷. The following Chinese characters can be found under 八 (丷) radical: 公, 分, 并, 兵, 第.