单项选择题
If you（）bright sunlight（）dry wood with a glass, it will start burning.
A.expose；to B.concentrate；on C.aim；at D.focus；on
单项选择题 When he was a young boy, a serious disease deprived him of the（）of hearing.
单项选择题 Stamping on any country's national flag is an（）to its people.
单项选择题 I am afraid that you have to alter your（）views in light of the tragic news that has just arrived.
