4. By the time Carl had arrived home, his mother left.
5. I will love you until you will die.
6. Whenever I am seeing Brett, I am getting sad.
7. Before he was waking up yesterday, he had a cup of coffee.
8. I work until I will finish the job.
9. By the time Kendrick had turned on the TV, the program had been
ended.
10. Shirley worked at that company since she moved to Connecticut.
Can anyone check the errors here please?

4. Correct, could be rephrased as 'By the time Carl got home, his mother had left'

5. I will love you until you die or I will love you to death

6. Whenever I see Brett, I get sad

7. After he woke up yesterday, he had a cup of coffee (saying before he woke up implies he drank some in his sleep)

8. By the time Kendrick turned the TV on, the program ended. (could also say 'had gone off')

9. Shirley has worked at that company since she moved to Connecticut

Explanation:

Proper phrasing, just need to change or rearrange words. Sorry if this wasn't right

the answer is:  

he is voicing feelings shared by all humans regardless of race.

in paul laurence dunbar's poem "we wear the mask," he replicates the words mask and we to emphasize how people in general -not just black americans- hide their true feelings. he suggests the masks cover people's faces and eyes, which are the main parts that display their emotions. he also thinks people's pain conceal behind those masks, so that they cannot see reality and nobody is able to see one another's sorrow.