【词汇讲解】
1.tarnished v. 使生锈，沾污
如：The firm's good name was badly tarnished by the scandal.这件丑事玷污了公司的好名声。
2.acidic adj. 酸的，酸性的
如：The soil becomes more and more acidic as pollution mounts up.随着污染的加剧，土壤的酸化越来越严重。
3.tenderizer n. 嫩化剂
4.pillowcase n. 枕头套
