主句是The tree was blown down.其中主语是the tree,谓语是was blown down.
that the farmer planted是定语从句,修the tree.其中,主语是the farmer,谓语是planted,宾语是关系代词that.
句意：农民种的那棵树被风吹倒了.
不明白的再问哟!请记得采纳,多谢!