重点讲解：
1. an alternative to 可供选择的；可供替代的；
例句：New ways to treat arthritis may provide an alternative to painkillers.
关节炎的新疗法可能是止痛药之外的另一种选择。
2. die of 死于……；
例句：The little match girl died of hunger and cold.
卖火柴的小女孩饥寒交迫而死。
3. account for （数量或比例上）占；
例句：Energy and resources now account for about 7% of the companies investments, up from 5% a year earlier.
能源和资源目前占公司投资额的约7%，高于一年前的5%。
4. according to 据…所说；按…所载；
例句：According to research, only one smoker in a hundred is able to kick the habit without some kind of help.
研究表明， 一百名吸烟者中只有一名能够不借助任何帮助成功戒烟。
