what is Level

Level[ n.]

1.等級; 程度，水平;

2.高度，深度

3.適當的位置

4.水平線;水平高度

5.平原，平地

e.g.
A relative degree, as of achievement, intensity, or concentration:

the local level of government; studying at the graduate level.
地方一級政府；研究生階段的學習

an unsafe level of toxicity; a high level of frustration.
毒性的危險度；極其憤怒

I finally found my own level in the business world.
我終于在生意場上找到了自己的位置

a platform at knee level.
齊膝的平台

即係 等級 嘅意思!!!