@misc{10818/33376,
year = {2018},
month = {6},
url = {http://hdl.handle.net/10818/33376},
abstract = {By the end of this lesson the student will be able to review the use present perfect tense, when to use it, how it is formed, and what to be careful with.},
publisher = {Universidad de La Sabana},
keywords = {Present perfect},
keywords = {Grammar},
keywords = {Adverbs},
title = {Present perfect part I},
author = {Manzur Henao, Tarek},
}