胚胎发育和母体子宫内环境同期化程度越高，妊娠率越高。（）
参考答案：对
在直角三角形中，若两条直角边长分别为6cm和8cm，则斜边上的中线长为 cm.
—You have made great progress recently.
—______.
A．So has Ann
B．So Ann has
C．So she does
D．So does she
