“is”的否定形式是“isn't”。
读音：is 英 [?z]美 [?z]
释义：vt.& vi.，是（be的三单形式）n.，存在。
双语例句
1、Beauty is an attitude. It has nothing to do with age.
美是一种态度，与年龄无关。
2、The best thing to do when entering unknown territory is smile.
踏入未知地带最好的对策就是微笑。
3、A miracle is something that seems impossible but happens anyway.
奇迹就是看似不可能，却发生了。
4、Failure is never quite so frightening as regret.
比失败更令人恐惧的是懊悔。
5、If you wait， all that happens is that you get older.
如果你等待，发生的只有变老。
