—Is the experiment easy? — ________ . I’ll just do my bit.
This is a difficult and stressful job, but one _____ you can really help people.
A feather falls slower than a stone only because the air holds the feather back more than it ______ the stone.
The old black woman used to tell stories under the tall tree, her grandchildren ______ around and ______attentively.
According to _______ recent report, large ice cream producers usually have better production record.
—I should have spent more time on English, otherwise I wouldn’t have failed in the exam. —You are right .