He is _____________ to go to school. [ ]
A. go
B. goes
C. to go
D. going
答案:D
简述现场总线的技术特点和体系结构特点。
肋骨骨折最常见于()
A.1~4肋骨
B.4~7肋骨
C.7~10肋骨
D.10~12肋骨
E.7~12肋骨