骨软骨瘤典型X线特征是（） A.瘤体可随骨骺生长而移至骨干 B.背向关节生长的骨性突

There were many choices for us to take exercise, but I'd like to___ the football club.    [ ]

A. join  

B. attend 

C. take part in 

D. join in

With spring ______, many cold-blooded animals are coming out to hunt food. [ ]

A. approached

B. approaching

C. to be approached

D. having approached

使用滚动导卫装置主要是为了提高产品的尺寸精度。

已知某井机型为CYJ5—2．5—26B，实际冲程为1．8m。冲程利用率是多少？

下列软件系统结构图的宽度为【 】