【多选】生物样品测定前要进行预处理,因为()。
A. 生物样品中被测物浓度低
B. 成分复杂,干扰多
C. 药物在体内以多种形式存在
D. 蛋白质对测定有干扰
E. 测定工作量大
everyone got excited with the grand (celebration) of the 70th anniversary of the founding of the People's Republic of China.
A. 对
B. 错
Chinese people are famous for their kindness and (hospitality).
A. 对
B. 错
When all the lost things were (presented) to the owner by the police, he could hardly believe it was true.
A. 对
B. 错