加ing:like doing,remeber doing,forget doing,prefer doing to doing,look forward to doing sth.,be used to doing suggest doing,prastice doing,enjoy doing,finish doing,mind doing,keep doing 加to do:like to do,want to do,get used to do.,used to do,determine to do,learn to do,expect to do,refuse to do,managed to do,pretend to do,promise to do,choose to do,was/were able to do