()缺陷对焊接接头危害性最严重。
A.气孔
B.夹渣
C.夹钨
D.氢致裂纹
参考答案:C
—My daughter has passed the exam.
—Congratulations! She’s really intelligent.
— .
A.No, she is nothing
B.Oh, thank you!
C.Sometimes she is intelligent
D.You are right
()、()、()、()、()、()可导致子宫增大。