本文对全能运动员赛前紧张和焦虑所产生的原因进行分析，并说明其对比赛所产的影响。
The paper analyzes the reasons of nervousness and anxiety of the all-round athletes before race, explains its effect on the race and points out that it is vital for the success to conquer them.
分析了厚料冲孔用冲头破损的主要原因，针对这些易产生的问题，设计了一种冲头，并说明了其特点。
This paper analyzes main reason why thick sheet piercing punch is easily destroyed, and design a new punch to above-mentioned problem and introduces its some characters.
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