Complex sentence: The immigration of the Copts to Canada might have started as early as the late 1950s, starting from the 1970s Canada recieved a higher number of these immigrants and this is still the case.
Split into simpler sentences: The immigration of the Copts to Canada might have started as early as the late 1950s. Starting in the 1970s, Canada recieved a higher number of these immigrants and this is still the case.