It is answer d. around forts is the adverb phrase and it modifies built
It can expand your vocabulary. context helps understand what’s happening without it being there.
reading helps you in all subjects. biology- helps you understand what your reading.
math- word problems
history- helps you fully understand what happened.
writing: helps you learn new words.
An introduction is given about how the topic of interes will be treated.
Usually images of an explanatory nature are included, with a explanatory talk, the images are included to bring the reciver closer to the topic of interest in a friendly way.
it's purpose is to inform a non specialized public, and sometimes, without prior knowledge, so that the same present an interest in the subject.
3.)3. Foreshadowing hints to readers that something is of significance and gets them interested.
4. Exposition helps readers understand the background of the story