劲头: 1.(力气) strength; energy2.(精神; 情绪) vigour; spirit; drive; zeal 短语和例子工作劲头很大的人 a whale for work; 看他们那股兴高采烈的劲头儿。 see how jubilant they are [look]. 他干起活来劲头十足。 he is full of drive in his work
松懈: relax; slacken; slack; loosening; lose momentum 短语和例子松懈斗志 relax one's will to fight; 学习松懈 slack off in one's studies; 松懈纪律 relax discipline; 责备某人工作松懈 speak to sb. about his slackness in wo