Complete the sentence : A secondary source is... (I'm poor so I can't give more points)

A secondary source in most cases, are made by authors not present during the event. Secondary sources include articles, history books, textbooks. They are used for researching but some of their ideas may be biased or incorrect.

the two sonnets of sidney most closely follows the division between the octave and the sestet are the astrophel and stella sonnets.

remember, the goal of an adjective clause is to add more information to a noun or a pronoun. as you can see from the examples above, you can add information by including a longer adjective clause or tighten up a sentence by turning the adjective clause into an adjective phrase.