A:将细胞与内环境分隔
B:控制物质进出细胞
C:进行细胞问信息交流
D:控制细胞新陈代谢
化学方程式aC2H2 +bO2cH2O+dCO2配平后a、b、c、d之和为( )
People are starting to use energy from the sun, wind and water because they cost very ________ and will never ________.
用下列词语造句
①授予
②崎岖