Editing  a  letter for the correct  use of  commas
dear callie,
it has been a fun, exciting vacation. the tour guide who has become a good friend is great! i think you would have loved this trip because you love excitement. after i get home, we should plan a trip together.
sincerely,
julia
choose the  best  revision of the sentence that contains the error.
the tour guide who has become, a good friend is, great!
the tour guide who has become a good friend, is great!
the tour guide, who has become a good friend is great!
the tour guide, who has become a good friend, is great!

The tour guide, who has become a good friend, is great!

Explanation:

The commas help separate the two ideas in one sentence correctly. A good way to check that this is correct is to remove the words separated by the commas - "who has become a good friend" - and check if the sentence still makes sense. In this case it would be "The tour guide is great!" which makes sense as a sentence. Thus, this version of the sentence is correct.

the sample answer on e2020

conflicting values are demonstrated between two different groups in animal farm. first, the farm animals value hard work. this is shown by them working late and working long hours at the request of the pigs. napoleon and the pigs, however, sleep late daily. furthermore, the animals value equality. this differs from the value of napoleon and the other pigs. instead of equality, they value only gaining power and maintaining their own privilege, which is demonstrated by their taking extra milk and sleeping in beds.

op: object of preposition