cement/concrete: Cement is a powder which, when mixed with water, sand, and stones, forms concrete. You are not standing on a cement floor; you are standing on a concrete floor.
refute: To refute an argument or accusation is to prove it wrong, to demolish it conclusively. This is seldom accomplished to everyone’s satisfaction. If you want to indicate that someone disputes or denies an accusation, write that he or she rebuts it.
stable condition: The conditions of hospital patients are rated as good, fair, poor, and critical. “Stable” is not a condition, no matter how often a police report says so; “stable” is an indication that the patient’s previously announced condition is unchanged. If you insist on using the meaningless stable condition, I will excise it and leave it that the patient is receiving hospital treatment.
toxin: A toxin is a poisonous chemical, but not all poisonous chemicals are toxins. A toxin is a poison of biological origin, such as snake venom or the botox chemical produced from the bacterium Clostridium botulinum for cosmetic purposes.