Only after spending several nights working on the math problem to wonder whether the problem was wrongly set.

The Japanese government stubbornly claimed the ownership of Diao Yu Islands belonging to China, ______ greatly hurt the friendship between the two peoples.

It’s not easy ___ me to talk with the foreigners in English.

We were having evening class ____ the light went out

Do you have enough to all your daily expenses? —Oh yes, enough and to spare.[ ]