English is the primary language used in the Toronto area.
While Canada recognizes both French and English as official languages, you are unlikely to find many services in French other than government services.
With that being said, there is a wide range of languages in regular use throughout the city, with stores and restaurants that cater to clientele from different nationalities and who speak various languages. It's a good idea for expats in Toronto to learn to speak English if they are not already fluent, but with the small cultural communities, many can get away with a limited knowledge of English.
There are many language schools in Toronto to help you learn English. Below is a list to get you started.
For a complete list of English schools in Toronto, click here.