根据句意和汉语或首字母提示，填写恰当的单词。

1. The pretty girl gave me a ________( 讨人喜欢的) smile.

2. I can't stand the terrible smoke that cigarettes _________(产生).

3. Very little of the house _________(遗留) after the earthquake.

4. Don't add salt to the dish. It's s         enough.

5. The ice will soon change into water if you h__________ it.

目前提出的降低多层CT剂量的措施之一是（）

A."不变焦点"技术

B."可变焦点"技术

C."焦点增大"技术

D."焦点减小"技术

E."焦点对称"技术