The meaning is what only I knew, but the problem is that each time, the word class seem to be used wrongly by me.
When I want to up, then each sentence I use "up", but, my teacher, it lmust be something wrong, because I read someone who come from England posted in forum somewhere else, they used some words like "upper" to express what they mean.
You see, what I'm interested in is aviation, so direction is the most important thing in that field, I never made mistake on direction of an aircraft, but I feel the words I used must be not right.
If I want to say "there is a bomb bay at downside of fuselage", everyone know what I mean, but some aircraft in which the bomb bay is not at downside, but left and right, then I check dictionary, I found no word spelling as leftside or right-side, then I found that word "upper" is a noun whereas "up" could be a. or ad. or prep. but for left, I never learned noun form of it. Herein everything go mess in my brain.
When I ask my friend of aviation forum, although they speak English, but all they reply my ask is "I know what you mean". But I want to learn perfect Englsih not Chinglish, please teach me each form of those direction words.
thanks in advance.