重点讲解：
1. be responsible for 负有责任的；应承担责任的；
The rebels were responsible for the mass murder of 400 civilians.
叛乱者对屠杀400名平民负有责任f;+dUXiYibrmZqTZP=。
2. thus far 到目前为止；
Thus far, the two prime ministers have achieved no concrete results.
到目前为止，两位首相还没有取得实质性成果8[7fhoEdrNR5#P,|。
3. simmer down 平息下来；平静下来；
I left him alone until he simmered down.
等他平静下来之后我才去找他Vf5+qvg6V)^r^。
4. at the invitation of 邀请；获得邀请；
A concert was held at the invitation of the mayor.
在市长的邀请下举办了一场音乐会yWBO+~988WYcFu。