加热炉炉膛负压增加，其烟气氧含量（）。
A.增加
B.降低
C.不变
参考答案：A
She's looking at me _______ she ________ me, but I've never seen her before in my life. [ ]
A. as if, knows
B. as if, knew
C. as though, knows
D. even if, knew
菌落
