"My boyfriend was working at school."
I wrote かれし instead of わたしのかれし and it was marked wrong. I think it's quite obvious thats kareshi is MY boyfriend. No japanese people would say watashi no kareshi
Wouldn't it be がっこうでつとめていました? When you do something at a location, you use で, when you GO to a location, you use に. I may, of course, be wrong in this particular situation.
But you would say "I go to school" 私は学校に行きます.
And "I study at school" 学校で勉強します.
つとめました would be good if the boyfriend 'worked' at school, but because he 'was working' at school, we use つとめていました.
ています imply a continuity in time. In present tense is means its happening while in past tense you imply it happened in a period of time just as in english you can say: i played basketball or i was playing basketball.
This is one of those that really needs a cleanup. The "cursor over" for "working" shows three possibilities - none of which are available in the list. The correct solution then shows "勤めて" for "working" - but that is not a possible answer either.
Not all the characters used in the 'correct' solution are offered to complete the translation.
Well... firstly - the tense. The first one is in present continuous "[I am] working" and the second one is a form to describe habits, future tense or that, that you are doing something in general but not at this very moment. And as the words themselves go - there is no much difference other than that, that when you say you work for a company you would use 勤めます and 働きます can be used more widely, like for an example a part-time job.