Come to think of it, (I wouldn’t use this here; to me this implies that this is a casual idea that you just thought of, not a musing on your past. Maybe use “looking back”) it was
my imagination that doesn’t exist in reality (I understand, but native English speakers wouldn’t say this. I’d say, “Looking back, this was an unrealistic expectation.” Or something like that.). Over the past 3 years, I've never
been away from English. Taking 2 to 3 lessons (per week?) not to get my English rusty,
teaching people at the same time learn from them (not quite a sentence. You need to give at least one of these grammatical phrases a subject.). However, since last February
when the virus started to seriously spread all over South Korea, large English
institutes have been affected directly, and it has been difficult to have students
in my class. Luckily, though, the one where I work (some people don’t like prepositions at the end of a grammatical phrase) opened its doors yesterday,
and I am over the moon to have at least some students and to help them to reach
their target goals. Generally speaking, (I’d use a different opener. This seems redundant.) it might not be just (redundant) a problem
for educational Insititues. It is more of a problem for large corporations, and
the HR people are not even sure when they are going to hire new employees, a problem which
is related to my job (not sure how correct my correction is lol, but it makes more sense I think). I am teaching students who want to get a job to meet
the requirement: they need to get an English test score. If this issue doesn't
stop, it will also be difficult for me to open my classes. When I first started
my career, I wanted to help people who want to change their lives and explore
something new by learning English, which I'd gotten through (“gotten through” is informal phrasing. Use “done myself”?) in the past. I hope it
will get better with the most effective vaccine in any country so we can all get
back to normal.