选择胶体金特性的错误描述()
A.胶体金多与免疫活性物质结合
B.对电解质敏感
C.光吸收波长与金颗粒大小无关
D.微小颗粒胶体金呈红色
E.较大颗粒胶体金呈紫红色
参考答案:C
It’s hard to ________ this kind of plant. You have to water it every day.
A.look for
B.look at
C.look after
D.look like
什么是社区社会组织?