Measure Words for Chinese Mandarin

Measure Words for Chinese Mandarin
One of the difficult grammar for me when I learn mandarin. In English structure we can see the sample like ‘a pair of leg’, ‘three bunches of bananas’, etc. How to use the correct measures words? The different measure words are used in different kinds of object. The most commonly using measure word is 个 ‘ge(4)’. This is normally used to count people too, but if want to more polite we can use 位 ‘wei(4)’
三个男人
三位男人
Two of above sentences means ‘three men’, but the second seen more polite.

How about to count the other object? Like a book, paper, animal, etc. For the large flat objects counted by 张, the round objects counted by 支. Example:

我有五张纸 pronounced ‘wo(2) you(3) wu(3) zhang(1) zhi(3)’� means ‘I have five sheet of papers’
你有一支笔 pronounced ‘ni(2) you(3) yi(1) bi(3)’ means ‘You have a pencil’