slacken
英 ['slæk(ə)n]
美['slækən]
	    - vi. 松劲,懈怠;变松弛;变缓慢
 - vt. 使缓慢;使松弛
 
英英释意
- 1. become slow or slower;
 - "Production slowed"
 
- 2. make less active or fast;
 - "He slackened his pace as he got tired"
 - "Don't relax your efforts now"
 
- 3. become looser or slack;
 - "the rope slackened"
 
- 4. make slack as by lessening tension or firmness