What is the most significant Manufacturing Industries in Canada?

I think you mean "What are ... " Surely, you expect to find more than one.

http://www.google.com/#hl=en&expIds=17259,17311,23756,24692,24878,24879,25752,25854,26101,26209,26218,26286,26340,26751,26789&sugexp=ldymls&tok=5G_sIeVwduMxfFXlHbpk3Q&xhr=t&q=significant+Manufacturing+Industries+in+Canada&cp=46&pf=p&sclient=psy&site=&source=hp&aq=f&aqi=&aql=&oq=significant+Manufacturing+Industries+in+Canada&gs_rfai=&pbx=1&fp=8b9dcbd6d27162f3

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