Glenn
一切皆苦
- 8 Jan 2004
- 7,842
- 200
There's a huge difference between them.
ga -- Marks subjects of sentences and clauses. John ga kita -- John came (John is here). Sakana ga oishii -- Fish is tasty.
o -- Marks direct objects of sentences and clauses. Sakana o taberu -- I eat fish. Biiru o nomu -- I drink beer. Hae o koroshita -- I killed a fly.
Notice that in the o example sentences that there aren't subjects. In Japanese, known information is usually omitted, so it's safe to assume that the subject of these sentences is the first person.
wa -- Marks topics of sentences. This is a bit difficult to grasp for native English speakers, because we don't mark topics like this -- we just understand that they're topics, whether we know it or not. Most times it's used like a subject marker, though. I can actually use the above sentences with wa, too, like this: John wa kita -- John came. Sakana wa oishii -- Fish is tasty. Sakana wa taberu -- I eat fish (but not meat). Biiru wa nomu -- I drink beer (but not wine). Hae wa koroshita -- I killed the fly (that we saw earlier; that we were talking about...).
I think that maybe this page will be useful in your understanding of wa, but it may take some time to really grasp it. Also, for basic grammar, I suggest browsing around that site (the link is in my sig).
ga -- Marks subjects of sentences and clauses. John ga kita -- John came (John is here). Sakana ga oishii -- Fish is tasty.
o -- Marks direct objects of sentences and clauses. Sakana o taberu -- I eat fish. Biiru o nomu -- I drink beer. Hae o koroshita -- I killed a fly.
Notice that in the o example sentences that there aren't subjects. In Japanese, known information is usually omitted, so it's safe to assume that the subject of these sentences is the first person.
wa -- Marks topics of sentences. This is a bit difficult to grasp for native English speakers, because we don't mark topics like this -- we just understand that they're topics, whether we know it or not. Most times it's used like a subject marker, though. I can actually use the above sentences with wa, too, like this: John wa kita -- John came. Sakana wa oishii -- Fish is tasty. Sakana wa taberu -- I eat fish (but not meat). Biiru wa nomu -- I drink beer (but not wine). Hae wa koroshita -- I killed the fly (that we saw earlier; that we were talking about...).
I think that maybe this page will be useful in your understanding of wa, but it may take some time to really grasp it. Also, for basic grammar, I suggest browsing around that site (the link is in my sig).
I'll remember that. I think I'll bookmark that page. 
