[yù fáng]
prevent; take precautions against; guard against
carry out the policy of putting prevention first in medical work
贯彻以预防为主的医疗方针
take special precautions
采取特殊的预防措施
prevent a disease from spreading
预防疾病蔓延
Europeans take melons for a preventive against seasickness.
欧洲人吃瓜作为预防晕船的方法。