具有下列哪种特点的生态系统较稳定( ) A.生物种类较少 B.食物链较长 C.食 发布时间:2017-05-03 11:51 │ 来源:www.tikuol.com 题型:选择题 问题: 具有下列哪种特点的生态系统较稳定( )A.生物种类较少B.食物链较长C.食物网中营养结构复杂D.食物链中的消费者较多
题型:选择题 连词成句。1. the in there park a river is . 2. flowers the there in are many park . 3. lake the isn't there farm a on . 查看答案
题型:选择题 用所给单词的适当形式填空。1. Keep your eyes __ (close) while doing eye exercises.2. Trees can keep water from __ (run) away.3. Do you still remember __ (see) me somewhere in Shanghai?4. He failed many times, but he didn't give up __ (study) math.5. People are pretty __ ( relax) about time in Columbia. 查看答案