Why is it called "The Hard Company" in the army?

The Company with Hard Life is also called The Soldiers with Hard Life in the Company with Hard Life. The lyrics are as follows:

Hard Company

Hard Company,

Hard Soldier,

Hard Thought is red,

Hard Bullets have a long eye,

Hard Bayonets are red with blood,

The impact is like a gale,

Sticking to the Great Wall of Iron, <

Extended information:

The Hard Company sings the feelings and greatness of soldiers. Due to the rapid development of modern society and economy, the pursuit of soldiers is also diversified. Many soldiers don't like to listen to and sing military camp songs, and their mouths are always humming some soft pop songs, which is extremely out of harmony with the youthful and energetic military camp. A hard company, a hard soldier and a hard soul are soldiers.

Reference: People's Network -77589 Unit 3 cultivates fighting spirit with cultural activities

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