( )不是钢筋冷拉方法的特点。
A.可使屈服点降低
B.材料变脆
C.伸长率降低
D.可制作预应力钢筋
参考答案:A
The number of students in our school 4000 and a number of them good at playing ping pong.
A.is, is
B.are, are
C.is, are
D.are, is
白癜风病因有以下几种学说:()()()()。