Look at the photos ____ I took in the Yellowstone National Park.
Of the two pens, the boy bought _________ expensive one at last.
We have an hour ____doing after-school activities, and two hours _____homework every day.
Linda finished her homework __________ than John.
I think PE is one of ______subjects of all.
The whole plan _________ the coming National Day _________ us too much time.