semi - arid areas的用法和樣例：
例句
- Arid regions cober arid and semiarid areas.
旱區包括干旱區和半干旱區。 - Desertification is a process caused by the conflict between the low productivity of the arid land and the ever increasing material and social demand of human beings.
沙漠化是由于干旱半干旱區土地很低的生產(chǎn)力與人民群眾日益增長(cháng)的物質(zhì)文化需要不相適應造成的。
