Her son died in her arms. She felt so much _______that she cried aloud.
A:painful
B:break
C:pain
①农田生态系统 ②海洋生态系统 ③森林生态系统④草原生态系统 ⑤淡水生态系统
紫菜____ 水稻____ 树蛙____ 鲤鱼____ 狮子____.
已知f(x)是偶函数,它在0,+∞)上是减函数,若f(lgx)>f(1),则实数x的取值范围是( )