例：Don't stand in the rain. 不要站在雨中。
The wind blew down the trees. 风把树刮倒了。
The ship sank in the storm. 船在风暴中沉没了。
The rain has cleaned the air. 下雨净洁了空气。
The fog was so thick that we couldn't see the top of the hill. 雾很大，我们看不见山顶。
提示
a 这类名词前有形容词修饰时，可用不定冠词，表示“一场，一阵，一种”
例：A cold wind is blowing from the north. 冷风从北方吹来。
There was a heavy rain last night. 昨晚下了一场大雨。
A heavy snow is falling outside. 外面正下着大雪。
b 这类名词表示一般物质时，不用冠词。
例：Rain falls in summer; snow falls in winter. 夏天下雨，冬天下雪。
Man can't live without air. 没有空气人不能活
The wind blew down the trees. 风把树刮倒了。
The ship sank in the storm. 船在风暴中沉没了。
The rain has cleaned the air. 下雨净洁了空气。
The fog was so thick that we couldn't see the top of the hill. 雾很大，我们看不见山顶。
提示
a 这类名词前有形容词修饰时，可用不定冠词，表示“一场，一阵，一种”
例：A cold wind is blowing from the north. 冷风从北方吹来。
There was a heavy rain last night. 昨晚下了一场大雨。
A heavy snow is falling outside. 外面正下着大雪。
b 这类名词表示一般物质时，不用冠词。
例：Rain falls in summer; snow falls in winter. 夏天下雨，冬天下雪。
Man can't live without air. 没有空气人不能活
