How can you_______?
—Let’s go out for a walk.—You’d better not. These days the air is getting much ________ than it was before.
You get wet all over. It must be raining ________ outside.
—Dinner is ready. Help yourself, please!—Wow! It ________ delicious. You are really good at cooking.
As a student, we should keep our classroom ________.
Some children prefer to eat junk food ________ it’s not good for their health.