差动牙移动技术的基础是 ()
A.Edgeise技术
B.Begg细丝弓技术
C.传统的直丝弓技术
D.Tip-edge差动直丝弓技术
E.当代直丝弓技术
参考答案:B
This maths problem is ______ that one. [ ]
A. not so easy as
B. more easy than
C. as easier than
D. easy than
什么是“速汇通”?