If you have no activity for a few minutes, you'll go 'offline' on the forums.. Meaning the little green (or red if you're invisible, for me) light next to your name will go grey.
In maths, they are positional offsets. So for example, if point A is (0, 2) and point B is (1, 4) then vector A-->B is 1i + 2j (in vector notation, that basically means (1, 2).
In programming (which you probably won't find on this JASS forum, vectors probably refers to the above) a vector is an unlimited array, or something. I'm not totally sure.
Is the school system in your country similar to Chinese school system? I could never imagine being a teacher in a Chinese school, what's expected of students and teachers is just so different from what I'd be looking for as a teacher
Yea I came last year. I was quarantined for about 30 days. Fml. The first day of my quarantine was the eve of Chinese new year last year. Fml again... Lol.