sert＝to join（结合）,to put（放置）
(a) [U] action of applying influence, etc 发挥; 运用; 行使; 施加
*Exertion of authority over others is not always wise; persuasion may be better. 利用权力压服别人并非永远是上策, 运用说服方法或许更为可取.
(b) [C, U] (instance of) great effort 努力; 尽力; 费力
*incapable of physical exertion 体力上不能劳累的
* He failed to lift the rock in spite of all his exertions. 他虽然竭尽全力, 但仍未能将那石块搬起.
* Now that I'm 90, I find the exertions of travelling too great. 我年届90岁, 出远门已力不从心.
n [U and C]
a lot of physical or mental effort
The afternoon's exertions had left us feeling exhausted.
the use of power, influence etc to make something happen
the exertion of authority
1. The doctor says he must avoid all exertion. 医生说他必须避免任何劳累。