Fill in the blanks (a) The insects, butterflies, honeybees and birds help flowering plants in .
(b) A forest is a purifier of and .
(c) Herbs form the layer in the forest.
(d) The decaying leaves and animal droppings in a forest enrich the .
Fill in the blanks (a) The insects, butterflies, honeybees and birds help flowering plants in .
(b) A forest is a purifier of and .
(c) Herbs form the layer in the forest.
(d) The decaying leaves and animal droppings in a forest enrich the .