The book ___ three yuan, but it only ___ me two yuan.

 In my opinion, both teachers and parents should ____ the students from playing computer games so much, which affects their studies and health.

If the opportunity would ______, hold on to it and don’t let it go.

 They are discussing how to ____a plan to advertise their new product in the office.

The accident produced a very bad impact on the society, so those who _________ the project were severely punished.