My chest           when I take a deep breath, doctor.

 The couple ________their old house and sold it for a vast profit. 

 ---I’m going to the supermarket, let me get you some fruit.---OK. Thanks for your _____________.

Li Lei cannot eat so big a watermelon. You have to cut it_______.

That hero who died in the war was so brave that he never ____ ____ to the enemies until death.