氟骨症病人血钙降低是由于
A.氟引起肾脏重吸收降低
B.血中氟与钙结合沉积于骨组织
C.氟促进血中钙形成盐类而排出体外
D.氟干扰钙的吸收
E.氟促进降钙素的分泌
参考答案:B
对于一次函数y=kx+3,如果y随x的增大而增大,那么k需要满足的条件是______.
句型转换,每空一词(10分)
小题1:That is my math book.(改为一般疑问句)
______________ _____________ your math book?
小题2:It is on the desk.(对划线部分提问)
______________ _____________ it?
小题3:Are these your cousins?(做肯定回答)
______________, _____________ are.
小题4:That is an English book.(改为复数句子)
______________ are English ______________.
小题5:His name is David.(改为同义句)
______________ _____________ David.