Why did WWI see so much death & very little land gained?

WWI saw so much death due to chemical warfare by the Germans and new artillery such as machine guns and tanks.

Explanation:

cultural/diplomatic relations. most medieval japanese   culture has chinese origins. writing, architecture etc.

the group i'm selecting: greeks.

a first group of greek immigrants came to the us in the 1850s. the second group came to america starting in the 1890s due to economic opportunities they didn't have back in their home caused by the hardships of ottoman rule. greek immigration was 90% male, many of them expected to work and return to greece after earning enough capital, but ultimately had to remain in the us after the greek genocide.