Which one of the following study materials is designed for use with a separate textbook?
a. study guide
b. dictionary
c. practical exercise
d. supplement

The correct answer should be A. Study guide.

Study guides are usually combined with textbooks from which you are supposed to study. They help you study more efficiently.

Most participles end with “ed,” “ing” or “en” for those formed from regular verbs. Irregular verbs create a variety of endings for their respective participles.Participles modify nouns and pronouns in the same manner that adjectives do.

In your case, written is the participle and the modified word is write