1. undertake有承诺的意思，undertake to do 承诺做某事意思是promise to do2. Ranil Wickremesinghe was sworn in as the new prime minister of Sri Lanka after a tumultuous few weeks.在经历了动荡的几周后，拉尼尔·维克勒马辛哈宣誓成为斯里兰卡的新总理。1.ADJ A tumultuous event or period of time involves many exciting and confusing events or feelings. 激动的; 混乱的• ...the tumultuous changes in Eastern Europe.…东欧的剧变。2.ADJ A tumultuous reaction to something is very noisy, because the people involved are very happy or excited. 欢腾的; 喧哗的• A tumultuous welcome from a 2,000 strong crowd greeted the champion.多达2千之众的人群热闹欢腾地迎接冠军。

3. 政策松懈可以用laxity

The laxity of export control authorities has made a significant contribution to the problem.

出口管理当局的松懈是导致此问题的重要因素。

But by holding fast to the dollar, Germany ended up importing America's laxity.

但是，由于紧盯美元，德国受到了美国宽松政策的冲击。