He has been absent ________ class for quite a long time.
Once a schedule is made, by strictly _________ it, you can avoid putting off till tomorrow what should be done.
—You have just 15 minutes to get to the airport.—All right, I guess I can ________.
Let’s make good use of our energy and_________ wasting water, electricity, paper and so on.
He needs to improve his skills if he __________ the gold medal at the 2016 Olympics.
The teacher warned ________ was caught ________ during the test would be punished.