[单项选择]The Canadian population is chiefly characterized by its (47)______ duality. In other words, most Canadian speak either English or French. (48)______their origins, most Canadians attend school, work and play in either the French or English language or, in some cases, in both. However, Canada has a variety of minority groups who keep__(49)______ cultural characteristics. For a long time the Canadian Government (50)______ a policy of assimilation. But it did not work. (51)______ from different countries still kept their own cultures, religions, languages, and ways of life. At school even the French-speaking children and English-speaking children did not enjoy learning each other’s language. So in 1971, the Canadian Government (52)______ a policy of multiculturialism, recognizing that cultural pluralism within a bilingual framework was the essence of the Canadian society. Accordingly immigrants may be instructed in at least one official language to help them become full (53)______ in