中医学理论体系，以（）为主导思想，以（）的生理、病理为基础。
参考答案：整体观念；脏腑经络
解下列方程
（1）x（2x+3）=4x+6
（2）x2-2x-399=0．
Nowadays there are still a number of students school at various grades due to a lack of money in some poorer areas.
A．leaving out
B．making out
C．letting out
D．dropping out
