钢筋混凝土预制桩的质量检验标准施工中应对桩体垂直度、沉桩情况、桩顶完整状况、接桩质量等进行检查；对电焊接桩，重要工程应做10%的焊缝探伤检验（）
参考答案：对
He never thought of it before, ________all that his parents had done for him for granted.
A．taking
B．taken
C．to take
D．took
暗箱
