A：He studies Chinese．
B：He does word puzzles．
C：He reads English．
小强同学在踢足球时，用力踢向足球，足球受力后腾空而起，球离开脚后能在空中继续飞行，是由于足球具有____，同时他也感到脚疼，说明物体间力的作用是____的.
—Hello, who can go to the Palace Museum with me tomorrow?
—Oh, sorry. _______ Jim _______ I can go with you; we have to take a test tomorrow.
