Under and underneath are synonyms. They mean almost the same thing, so just replace "underneath" in the sentence with "under".
It is as if a great earthen pot has dropped from an unreachable rafter,what is the grammatical name and function
D. parallel structure just means that all of your verbs in the comma series line up in regards to tenses, here. in choice D, it's "BE friendly," "INTRODUCE yourself," and "SMILE." these are all present tense verbs.
the rest of the choices don't match--"exercise" and "stretching" are two different verb forms in choice A, "to go to the library" is the odd one out in choice B, ane "to build" doesn't match with the "-ing" verbs in choice C.
