中国历史上第一个全国性的专职警察机构是1898年在长沙成立“巡警部”。( )

短文改错。

     My mom learned early on how to cook for a large family. Grow up on a small farm, she was the

old of seven children. So you can imagine responsibility that fell on her shoulder. She mom taught her

how to make pies and can fruits and vegetables. She lets her make meals for companies, too. As a

wife and a mother, mom baked and cooked even much, because I have six brothers and four sisters.

With so a large family, mom was always make delicious dishes while we were growing up. She always

used the freshest herbs and vegetables from our garden. And for each birthday, she would make the

birthdaychild's favorite meal.

下列元素的元素符号书写错误的是（　　）

A．氮  N

B．磷  P

C．硅  Si

D．锰  mN

用溶血标本测定血清电解质浓度时会出现

A．钾离子偏高
B．氯离子偏高
C．钙离子偏高
D．钠离子偏高
E．钙、钠离子偏高

属于替牙期间的暂时性错是（）。

A.多生牙导致上颌左右中切牙萌出早期出现间隙

B.上下恒切牙萌出早期，可出现前牙反

C.上颌侧切牙初萌时，牙冠向近中倾斜

D.上下颌第一恒磨牙建初期，为完全远中关系

E.恒切牙萌出初期，出现轻度拥挤

简述ERP的作用。