1 . The difficulty which we had c_______ (交流) with the local people has now been removed.

2 . I was about to give up ___ my father came and encouraged me to keep going. （用适当的单词填空）

3 . Some people think that the great Chinese scholar Confucius, __________ lived from roughly 551 to 479 B.C., influenced the development of chopsticks.（根据句意填空）