Just like fingerprints, each person’s DNA is ________unless he has a twin.

llyspeaking, according to thedirections, the drug has no side effect.

下列各组句子中，不含通假字的一组是（      ）

She didn’t make ______ great progress，did she_______，although she did her best.

We are lucky to be among thegeneration of people who have ________ and experienced the great social changesin our country.