double(sb)up/over
—phrasal verbwithdoubleverb[IorT]uk/ˈdʌb.əl/us/ˈdʌb.əl/
If youdoubleup/over, or if somethingdoublesyou up/over, yousuddenlybendforwardsand down, usually because ofpainorlaughter.
（通常指由于痛苦或大笑而）弯腰，前仰后合
Most of thecrowddoubledup withlaughterateveryjoke.人群中的大多数人每听完一个笑话都会笑得前仰后合。
She wasdoubledup/overwiththepainin herstomach.她肚子疼得直不起腰来。