下列各物质组成中含有糖类物质的是[ ]
A．RNA
B．性激素
C．胰岛素
D．生长激素
答案：A
如果a2x+1≤ax-5（a＞0，且a≠1），求x的取值范围。
句型转换。
1. She likes to look at the flowers. (改为一般疑问句)
she to look at the flowers?
2. Jump in! (改为否定句)
jump in!
3. Jenny likes to swim. (用skip改为选择疑问句)
to skip?
4. He feels scared. (就画线部分提问)
he feel?
5. Sometimes he plays soccer. (就画线部分提问)
he soccer?
