Optimal search tree

optimal ['ɑptəml]

adj. 最佳的，最优的;最理想的;

opt =bext,表示”最好, 期待, 愿望”

search [sɝtʃ]

v. 搜寻，搜索;调查;搜查;探求; n. 搜索;调查;探求;

tree [tri]

n. 树;木料;树状图;宗谱; vt. 把…赶上树;使处于困境;把鞋型插入（鞋内）;

All right. Please hold two orchestra seats for us.

好，请帮我们保留两张前排的座位。

Don't mention it. I hope you can come again soon.

不用谢，希望你不久能再来。

You were very kind. You brought out all your jewellery and you told me I could take anything I wanted. There were so many beautiful things that it was hard to choose. And then I saw a lovely diamond necklace with a big blue stone in the centre.

你太好了。当时你把所有的珠宝首饰全都拿了出来，而且说，我要什么就可以拿什么。漂亮的首饰太多了，实在难挑选。后来我终于看中了一条美丽的钻石项链，中间还嵌着一颗大蓝宝石。