E.coli can be helpful and harmful at the same time if you know what i mean. E.coli produces a toxin that can be very harmful to people. Also,e.coli is helpful because it help digest your food.
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it can be helpful or harmful
sometimes they are helpful and harmful.
Sandpaper is both helpful and harmful.
they are helpful not harmful to plants
helpful
helpful
Depends on what part of "harmful" or "helpful" you are referring to.
Harmful bacteria will harm you. Helpful bacteria will help you.
Slash and burn does not sound helpful, it sounds harmful.
helpful
Helpful.