direction confused

[zhengrong]

I always used wrongly on these words. Who would please to help to summarize all of words concerning direction?

up--- upper----- upside---- upward ?
down--- under---- underside----- downward ?

front---- frontal---- foreside----- foreward ?
back---- rear---- backside------ backward or rearward ?

left---- sinister---- leftpart/leftside----- ?
right---- dexter---- rightpart/rightside?---- rightward?

You may think I am drunk, but these really make me exhausting
I did some endeavors to check each kind of six dictionaries I had, but still confused, because using methods of these words looks far different from Chinese in which each word has fixed using way with different former. But in Englsih, I always make mistake of them.

[David L.]

Firstly, are you confident that you know what the words below mean and how you would use them?:
up
down
left
right
front
back

[zhengrong]

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.

[David L.]

Let's take it a bit at a time.
You understand what 'pick the pencil up' and 'put the pencil down' mean. So let's look at 'upper' and 'lower'

In the front of a Jumbo, there are two passenger decks. You have to go up some stairs to get to the upper deck, and 'upper' distinguishes it from the other deck, the deck that you walk on to when you enter the plane. In relation to the upper deck, this deck (the one as you walk on to the plane) is located at a level in the plane lower than the top deck, and so is called the 'lower' deck.


'upper' as a noun refers to a layer of leather in shoes. There are two layers- a top layer and a bottom layer. In relation to each other, one piece is upper, and one piece is lower (in the shoe). Also, in false teeth (dentures), those that go in the top part of the jaw are called 'uppers', and those that go on the bottom of the jaw are called 'lowers.' This is a short way of saying, 'the upper set of teeth and the lower set of teeth'. (With drugs, colloquially some drugs are referred to as 'uppers' because they elevate the mood, cause one's mood to go up. Those that make a person's mood go down are called 'downer's.)
So : the upper deck is situated higher in the plane than the lower deck. The lower deck is situation lower in the plane than the upper deck.

OK so far??

[zhengrong]

Sorry my teacher:

That's not enough

you see the up could be an adject, so we can say "an up surface", and it also can be a noun, so we can use "upper" instead of "up surface"
So there are twocouple of antonym
up - down for adject
upper - lower for noun ?? if I'm wrong correct me

then I want more

1) how about right and left? I'm seaking noun of them
2) rightside and leftside which meaning is a little different from right and left, so I am looking for these kind of form of "front" and "back".