Canada is a country _____many different nationalities as well as one with foreign immigrants _____ the majority of its population.

Some experts say _______ birthrate of Chinese, after the one-child policy is relaxed, can see _______ modest increase in future.

The Silk Road was ______ long that it passed through many countries.

Sam doesn’t like playing ____piano，but he likes playing ____soccer.

(2013·高考浙江卷)The children，________ had played the whole day long，were worn out.