以下关于细菌和真菌的描述,正确的是( )
A:都是单细胞生物
B:通过与动植物共生而使其患病
C:必须生活在有氧的环境中
D:主要作为分解者参与物质循环
_________ he was exercising in the park yesterday morning, he found a purse under the tree.
已知:TiOSO4遇水会水解.
The students four groups to discuss the topic.