― Where do you sit, Peter?

― I sit          Millie. She is just on my right.

A．next to

B．in front of

C．before

D．behind

来自口唇、颊肌和舌肌产生轻力作用于牙齿的阈值是（）

A.4小时

B.6小时

C.8小时

D.10小时

E.12小时