When we are very sad,we should think of          .

      professional violinist practices for several hours a day ,but       violinist has his own way of playing the Beethoven concert.

 -–What do you think of the lecture?--____but interesting, but I’ve managed to survive it.

Generally speaking, the culture and customs of America are like _____ of Canada.

At our factory there are a few machines similar to________described in this magazine.