The results showed that main factors were artificial breeding skill, cost, ration and feeding skill, labor difficulty, live beef market, butcher skill, etc.

调查结果表明，主要的影响因素有：人工授精技术、推广经费问题、饲料与饲养管理技术、肉牛销售与市场、肉牛屠宰加工技术等等。

youdao

Emotional labor can lead to difficulty in sleeping and family conflict.

情绪劳动会导致睡眠困难和家庭冲突。

youdao

Rural economy and society face the enormous difficulty, which has made strong thrust for the surplus rural labor to enter urban region.

农村经济和社会面临巨大的困难，为农村剩余劳动力进入城市施加了强大的推力。

youdao

Adam Ozemik has two thoughtful pieces up ( here and here) on the economics of unions and the difficulty organized labor faces in a global, dynamic economy.

FORBES: The Economics of Unions

While adequate weight gain during pregnancy is important for proper development of your baby, we now know that gaining too much weight is not good, as it can cause problems such as gestational diabetes, preeclampsia, increased risk of Caesarean section and infection, and more difficulty during labor.

CNN: How can I safely control my pregnancy weight gain?

One criticism of my proposal states that I ignore the difficulty in organizing labor unions.

FORBES: Yes, Unions Need Reinventing