【单选题】P2.下列关于对象“更新前”事件的叙述中,正确的是()。
【单选题】按用途和结构划分,“其他应收款”账户属于( )。
【判断题】水泵叶轮的功用是将动力机的机械能传递给水,转变为水流的动能与压能。( )
【单选题】What does the author suggest in this passage?
A.
You should not learn grammar only.
B.
You should ignore the rules of pronunciation.
C.
You should learn a language by mistakes.
D.
You should learn a language at school.
【单选题】制备的标准溶液浓度与规定浓度相对误差不得大于().