要求钨极具有()、施焊损耗小、引弧和稳弧性好等特性:
A. 电流容量小
B. 电流容量大
C. 电极压降小
D. 电极压降大
'Affix hopping refers to the bound morphemes in the verb group hop backward to join the following member in the verb group .()
Consonants are sounds made by a closure or narrowing somewhere in the vocal tract.()
钢铁的有害杂质()。
A. Mn
B. Ti
C. Fe
D. P