natural gas

gas found in the earth's crust, not manufactured 天然气.

National Trust, nationalism, nationalist, nationalistic, nationality, nationalization, nationalisation, nationalize, nationalise, nationally, nationwide, native, native speaker, native-speaking, nativity, nativity play, NATO (also Nato), natter, nattily, natty, natural, natural childbirth, natural history, natural law, natural philosophy, natural selection, naturalgas, naturalism, naturalist, naturalistic, naturalization, naturalisation, naturalize, naturalise, naturally, naturalness, nature, nature study, nature trail, naturism, naturist, naturopath, naturopathic, naturopathically,