Nikon Lens For Canon Camera

Chris asks…What is the best lens to get for my canon 500d (photos of equestrian sports)?I'm a ameteur photographer and I'm pretty good with a my camera but I'm looking for some advice about what lens to get. I've been told that Canon isn't the best to use for sports and that I should have got a Nikon, but I adore my camera! I will also need a lens that is compatible for taking videos and such like. I want it to be of a good quality too. Thank you! Your advice will be greatly

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