necessary

a.必须的；必然的 n.(pl.)必需品

near by, near to, near-, near-royalty, near-sighted, near-sightedness, nearby, nearest, nearly, nearness, nearside (also near), neat, neatly, neatness, nebula, nebulae, nebular, nebulous, necessaries, necessarily, necessitate, necessitous, necessity, neck, neckband, neckerchief, necklace, necklet, neckline, necktie, neckwear, necr(o)-, necromancer, necromancy, necropolis, nectar, nectarine, NEDC, nee, need,