The experiment show that proper amount of exercise, if ________ regularly, can improve our health.
He is always ready to help others, seldom, _____, refusing them when they turn to him.
After greetings the teacher said to his students, “Today we will _____ the lesson where we left off yesterday.”
_____ in her maths homework, Amy kept thinking and writing for an hour in her study.
They were in great need of help then. Therefore, your timely support certainly made a(n) _____.
When first seeing Masaccio’s paintings, people were convinced they were looking through _____ hole in _____ wall at _____ real scene.