A: Whose jeans are they?
B: They're my .
A:sister
B:sisters
C:sister's
某地发生民工中毒,为误食亚硝酸钠(NaNO2)所致,亚硝酸钠中氮元素的化合价是( )
下面句中只有一处错误,请找出并改正。
I'll come back after two days.
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