I want to work as an English translator

I didn`t consider other kinds of jobs like call center jobs, because they need to spend all their time at work, thus I am a storekeeper. The problem is that I have Raynauld's disease and I should be careful if its cold, so I want find a good job before the winter.
I failed a test 2 weeks ago for a translator's job and I can take it again only after another half year, thus I want improve my English to pass this test.

I passed a few units of English Grammar In Use and I want the test on what I remembered. There was a comparison of Present Perfect and Past Simple, and there were a lot of exceptions on how to use correctly various sentences.

So, we should use Present Perfect if the action or whatever isn't completed until now. For instance, "I haven't passed the test" means I'm passing it right now or I haven't started to pass it yet. But "I didn't pass the test" means that I had a test and I failed it, or, the action is completed.
There may be auxiliary words for defining tenses: last night, this week, since last year, 10 minutes ago. According to the words we have the rule: don't use Present Perfect when we talk about finished time. For example. I didn't eat a banana last week/tomorrow, but I haven't eaten a banana since Friday/ this week/ today.

Very well written!