名词变形容词：
1．名词后加-y,如：
luck→lucky,cloud→cloudy; wind→windy; rain→rainy;
sun→sunny,snow→snowy noise-noisy health→healthy
2．在名词后加-ly,如：
friend→friendly love→lovely day→daily
3．方位名词加-ern,如：
east→eastern west→western south→southern north→northern