sometimes they are helpful and harmful.
If you need help I recommend you type in the specific question you need help with
it can be helpful or harmful
Bacteria can be both harmful and helpful
Sandpaper is both helpful and harmful.
they are helpful not harmful to plants
harmful
Depends on what part of "harmful" or "helpful" you are referring to.
helpful
Helpful
helpful
Harmful bacteria will harm you. Helpful bacteria will help you.
chipmunks are harmful and helpful a by: Orlando on 02/29/08