铸造支托的长度一般为（）

A.磨牙近远中径的1/4

B.磨牙近远中径的1/3

C.磨牙近远中径的1/2

D.双尖牙近远中径的2/3

E.双尖牙近远中径的1/2

"______" means "to have, show confidence or pride in one’s worth, good character, ability, .etc".

A. To ride one’s high horse



B. To keep a straight face
C. Not to bat an eyelid



D. To hold one’s head high