Having parallel structure means
building sentences that are the exact same length
creating sentences that have the same tone
using the same verb tense throughout a sentence
writing two different texts at the same time

in the 1890s, southern states enacted a new form of black codes, called “jim crow” laws. these laws made it illegal for blacks and whites to share public facilities. this meant that blacks and whites had to use separate schools, hospitals, libraries, restaurants, hotels, bathrooms, and drinking fountains.

explanation:

sorry idk this one sorry i cant u

even though there may be variations in human emotions over time, the poem “ a contribution to statistics” by wislawa symborska suggests that the only unchangeable characteristic is mortality.

the author poses a distinction between the approximate and non-approximate numbers which correspond to our need for certainty in life and the difficulty of achieving it. our efforts to measure the exact often fail because the world is not always clearly structured .the poem seems to imply   that the only thing that is certain and has an exact number is death.