The largest ethnic groups are Newar (29.6%), Matwali (25.1% Sunuwar, Gurung, Magars, Tamang etc.), Khas Brahmins (20.51%) and Chettris (18.5%) . Tamangs originating from surrounding hill districts can be seen in Kathmandu. More recently, other hill ethnic groups and Caste groups from Terai have come to represent a substantial proportion of the city's population. The major languages are Nepali and Nepal Bhasa, while English is understood by many, particularly in the service industry. The major religions are Hinduism and Buddhism.
Along with Nepali, what is Kathmandu's main language? (If the question is unanswerable, say "unanswerable")
Nepal Bhasa