We often think insects to be harmless. This is partly true. Many an insect are harmful. Flies carry diseases. Others insects carry diseases, too. Farmers are at war with insects most the time. Hunger insects kill crops in the fields Farmers spray the field as to get rid of these insects. Does this means that all insects are harmful? No. Many are of great helpful to man. Bees make honey. With bees and other insects, many trees would have not fruit. Silkworms make silk. Some insects eat other insects that kill fruit trees.