个体难以清楚陈述、只能借助于某些作业形式问接推测其存在的知识是（）
A.感性知识
B.命题知识
C.程序性知识
D.陈述性知识
参考答案：C
（）she seemed to find English very difficult, but later he made very good progress.
A.At the first
B.At present
C.At the present
D.At first
硫化氢是一种（）气体。
A、无色、剧毒、强酸性
B、无色、剧毒、弱酸性
C、有色、剧毒、强酸性
D、有色、剧毒、弱酸性
