来自费栋的问题
英语定语从句Themostimportantchemicalcatalystonthisplanetischlorophyll,inthepresenceofwhichcarbondioxideandwaterreacttoformcarbohydrates.请问inthepresenceof在句中作什么成分?为什么要放在which之前?
英语定语从句
Themostimportantchemicalcatalystonthisplanetischlorophyll,
inthepresenceofwhichcarbondioxideandwaterreacttoformcarbohydrates.请问inthepresenceof在句中作什么成分?为什么要放在which之前?

