How to find a unit in the application questions?

How to find a unit in the application questions?

Look for keywords such as yes, Zhan, Bi, and so on
Example: A is 2 / 3 more than B. B is a unit
The number of boys accounts for 3 / 5 of the class, and the total number is unit one
Xiaohong's apple number is 1 / 3 of Xiaogang's. Xiaogang's apple number is one unit