---It is selfless ______ the doctor to devote all the time he had ________ for the patients.--I think so, they are so great.
—What’s the matter________your computer? —It doesn’t work.
The problem is________difficult that nobody can work it out.
—Smoking is bad for your health. —You’re right.I decide to________.
—How did he use to go to school? —By bike.But now he’s used to________to school.
Do you know the man________is talking with the teacher?