ことが、ものが、

[josiah]

since starting my japanese studies, these two words, grammar structures in sentences have been a constant thorn in my side and none of my japanese friends have been able to successfully explain their usage to me.
so when in doubt. turn to the forum!
how do i use these two words in sentences and is there a lesson that covers it, i have been unable to find one either.......

[Javizy]

Don't you have some examples of sentences you find difficult? ことが and ものが aren't grammar points in themselves, but since both こと and もの are nouns, naturally they take the particle が from time to time. Is there any particular function of either of the words that you're having problems with? They both have pretty broad uses, so it'd be quite a bit of explaining to answer your question.

[Jason]

While both こと and もの can mean 'thing" they're different in nature. もの is used to refer to physical things like objects and people. こと is used to refer to abstract sort of things like thoughts, ideas, and events.

I'm not sure if that answers your question though since I'm not really sure what you're asking.

[jkeyz15]

mono is like real, and koto like an abstract thing.

[josiah]

i know the concept on mono and koto and what they mean, and i know there is a lot of different grammar behind there usage, and i can understand a sentence with koto or mono from simply the other words and context,
but i don't know if there's been any specific lessons covering how to use it in a sentence,
i mean i'm not really sure what i want to know, maybe the different ways that it can be used in a sentence

[Javizy]

They can both be used as standard nouns meaning 'thing' in the abstract/corporeal sense described already:
ジャイアンが面白いもの見せるから、呼んでこいって。
Giant told me to get you because he has something cool to show you.
ばかなこと、言うんじゃねぇ。
Don't say stupid things / don't talk crap.

Following a plain verb「こと」acts as a nominaliser in a more abstract sense than「の」:
見ることは信じることだ。
Seeing is believing.

To say something is being decided on (voluntarily) in the phrase「ことにする」, basically like a standard 「にする」with a nominalised verb:
毎日30分勉強することにした。
I decided to study for 30 minutes a day.

In the phrase「ということ」, to clarify meaning, and to repeat hearsay:
明日のパーティーに行けないっていうことか。
Does that mean you can't go to the party tomorrow?
夕べ初雪が降ったということです。
They say the first snow of the year fell last night.

As an alternative (more formal sounding) way of expressing the potential,「ことができる」:
漢字を少し読むことができる。
I can read some kanji.

Referring to a past action in the phrase 「~たことがある」:
殺し屋1を見たことがある。
Have you seen Ichi the Killer?

I think that's all I can hack at the moment. There are loads more, and you can't really just use the context to understand them because they're idiomatic so the words themselves don't make a whole lot of sense, as you can see in some of these ones. It's going to take a bit more than reading these short explanations to master them as well, so I'd recommend buying a decent grammar reference.