1.MR GALANG has been studying medical tecnology for doctorate program at columbia university for about two years. we can also say.medical at technology.....by m

1.MR GALANG has been studying medical tecnology for doctorate program at columbia university for about two years.
we can also say.medical at technology.....by mr galang for doctorate program at the university
2.the jenitor of the school works at the school since 2015.at present he still works there.
he will get retired by 2019 this year.
the janitor of the school.....there for about 3 years