narrow - ad. limited in size or amount; not wide; having a short distance from one side to the other
nation - n. a country， together with its social and political systems
native - n. someone who was born in a place， not one who moved there
natural - ad. of or about nature; normal; common to its kind
nature - n. all the plants， animals and other things on earth not created by humans; events or processes not caused by humans
navy - n. the part of a country's military force trained to fight at sea
near - ad. not far; close to
necessary - prep. needed to get a result or effect; required
need - v. to require; to want; to be necessary to have or to do
negotiate - v. to talk about a problem or situation to find a common solution
neither - ad. not one or the other of two