Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks from 31 to 35.

The Magic of Pop-up Books

Books are normally thought of in terms of the pages that are looked at. They are simple, two-dimensional objects that we read. There are words on the page and occasionally ___(1)___ that help us see more clearly what the words are being used to describe. They are sources of knowledge, but more often than not they aren’t considered very special.

Some books take it another steps further, though, and their pages jump ___(2)___ and form three-dimensional objects. These books can make adults smile and cause children to be wide-eyed with ___(3)___. Called pop-up books in our times, they have been around longer than most people think they have.

Pop-up books were originally called mechanical books, and these paper ___(4)___ took a lot of work to make. They were not for children at all, although centuries ago there were practically no books made for children. The mechanical books helped illustrate ___(5)___ things as the phases of the moon or were used to teach complex theories.