煤的物理性质与化学性质主要与煤的成因有关，还受到矿物质、水分和煤化程度的影响。
参考答案：对
郑氏始孔子鸟既有鸟类特征，又有爬行类特征，这说明鸟类起源于
A．古代的昆虫
B．古代鱼类
C．古代爬行类
D．古代哺乳类
The more I think about him, the more reasons I find for loving him___i diD.
A. as much as B. as long as C. as soon as D. as far as
