因素factor; reasons or situations that determine success or failure of a thing
隐痛secret anguish/pain; indistinct/vague/dull/obtuse pain
饮食food and drink; eat and drink
移行divide a word with a hyphen at the end of a line and continue at the beginning of the next
优生优育bear and rear better children
有机磷中毒organophosphorus poisoning