【简答题】什么是生态系统?生态系统的共同特征是什么?生态系统的基本结构由哪几个部分组成,各组成成分包括什么?
【单选题】生态系统的基本组成部分是______。
C.
非生物环境要素、植物——生产者有机体、动物——消费者有机体、微生物——分解者有机体
【多选题】在灰平衡中,下列关于黑版作用的描述正确的是()
B.
黑墨比其它颜色的油黑更难提取,更有表现力,因而价格也最贵
【单选题】When the sentence "The had made a mess of the house" is turned into passive voice, which of the following is CORRECT?
A.
A mess had been made in the house.
B.
A mess had been made by them.
C.
The house had been made a mess of.
D.
The house had been made a mess.
【单选题】It started raining,so she__________ the nearest house.A.made forB.made off
A.
It started raining,so she__________ the nearest house. A.made for
【单选题】When the sentence "They had made a mess of the house" is turned into passive voice, which of the following is CORRECT?
A.
A mess had been made in the house.
B.
A mess had been made by them.
C.
The house had been made a mess of.
D.
The house had been made a mess.