While watching television, ________.
20. This printer is of good quality. If it _______ break down within the first year, we would repair it at our expense.
19. The teacher asked us to write a ________ article.
18. I used to be a very delighted girl. I guess no human being could have passed _______ childhood.
17. The new outline will throw light _______ students’ understanding of history.
--- Well, Linda, I’m sorry but I have to leave. --- _______. I hope to hear from you soon.