The earthquake of 2008 was extremely terrible. ___ it was the worst disaster we had ever seen.
The two friends had a quarrel about money, but shortly afterwards they shook hands and ________.
In the 21st century, all nations must take their ________of responsibility for the global safety.
-----How good the news is for you! ------ ______________.
What worried the mother most was __________ the Internet after class in this school.
------- Jack, you erase the blackboard today, __________? ------- But I did it yesterday.