Complex sentence: The majority of the population of Nuwara Eliya city is Sinhalese, there is however sizable communities belonging to other ethnic groups, such as Indian Tamils and Sri Lankan Tamils.
Split into simpler sentences: The majority of the population of Nuwara Eliya city is Sinhalese. There are sizable communities belonging to other ethnic groups, such as Indian Tamils and Sri Lankan Tamils.