可在尿中出现的胆红素是（）
A.未结合胆红素
B.结合胆红素
C.肝前胆红素
D.间接胆红素
E.与白蛋白结合的胆红素
参考答案：B
On his way to the airport, it ______ him all of a sudden that he had forgotten her birthday.[ ]
A. hit
B. knocked
C. occurred
D. beat
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