下列不属于先张法施工工艺的是（）。
A、预应力筋铺设、张拉
B、浇灌混凝土
C、放松预应力筋
D、孔道灌浆
参考答案：D
Kevin was not good at Chinese at first. After two months in China, _____, he made great progress.
A．while
B．but
C．however
D．otherwise
