维生素PP是NAD+和NADP+的组成成分，后者是（）的辅酶。
参考答案：不需氧脱氢酶
_____________ (有) a _____________ (树) near the river.[ ]
A. There is, trees
B. There are, tree
C. There is, tree
Missing school to watch the football is quite impossible. Which of the following can replace the underlined part.
A．out of the question
B．out of question
C．without question
D．beyond question
