@misc{10818/33374,
year = {2018},
month = {6},
url = {http://hdl.handle.net/10818/33374},
abstract = {By the end of this lesson the student will be able to review the use of present perfect tense in negative form and some adverbs.},
publisher = {Universidad de La Sabana},
keywords = {Present perfect negative},
keywords = {Grammar},
keywords = {Time expressions},
title = {Present perfect part II},
author = {Manzur Henao, Tarek},
}