A beam of light will not bend round corners unless ____ to do so with the help of a reflecting device.

A) increasing B) increase C) to increaseD) have increased

A) except for B) besides C) except that D) because

A) come B) to come C) coming D) having come

A) must fall B) must have fallen C) should have fallen D) can have fallen

A) will graduate C) will have graduated

B) will be graduated D) will be graduating

A) to learn B) learning C) to be learned D) being learned

A) No matter how C) Though B) Regardless D) Despite

A) Having seen C) Seeing B) To see D) Seen

A) not for, but for C) not that, but that

B) not as, but as D) not since, but since

A) so that B) that C) that is why D) so