Noun - a person, place or thing, e. g. human, Australia, computer. A name is kind of similar, it's a designation for a particular instance of a noun, e. g. Wilso.
Pronoun - I don't really know the actual definition but essentially it's a specific part of speech that subs for a noun, e. g. he instead of Wilso or it instead of horse. Since pronouns can be somewhat vague, their subjects have to be introduced first in a sentence or paragraph. E. g.
I'm talking to Wilso. He's from Australia. Pronouns are divided into first person singular (I), second person singular or plural (you), third person singular (he, she, it, one), first person plural (we) and third person plural (they). There used to be a differentiation of second person singular and plural (the singular used to be thee/thou) but that's archaic and not used any more.
Verb - an action word, but some are also used as a piece of defining participles (e. g. have is used to help denote past tense). The most common verbs are probably be, do, have and make. A pronoun plus a noun is used in conjugating.
Conjugations are used in order to understand how various verbs go along with various pronouns. French and other Romance languages illustrate this better than English does, but there are still English conjugations, i. e.
Code:I am we are
you are you are
he is they are
Most English verbs just conjugate out to 2 present tense forms, 1 is with a final s and the other is without. The one with the final s is the one used with third person singular, i. e.
Code:I walk we walk
you walk you walk
he walks they walk
Verbs that end in a vowel (like do) have some slight spelling variants in order to get the s at the end (e. g. does) but they conjugate in the same fashion. To be, which I conjugated above, is the only truly irregular verb in English. In contrast, there are lots of irregular verbs in French and Spanish and other languages.
Verbs come in various tenses, which describe time. There's a present tense, a past participle, a future tense, a conditional tense and what's called in Spanish the preterit, which is similar to the present tense but involves what's called a gerund in English. There are undoubtedly other tenses that arise when other words are combined, but let's go with these for the moment. The present tense is
walk, the past participle is
have walked, the future tense is
will walk, the conditional is
would walk and the gerund is
is walking. All verbs also have a second past tense, the past imperfect (at least I think that's what it's called; I'm having a devil of a time finding it). This form does not need the word
have in front of it. E. g.
I ate versus
I have eaten. Sometimes these two past tense forms are identical -- you can say
I walked and
I have walked. There are also transitive and intransitive verbs, but personally I've never heard a good definition of them.
Adjective - a word modifying a noun. Colors are adjectives, but so are words like emotions and other states of being. e. g.
The happy horse, the red wagon, the tall building.
Adverb - a word modifying anything but a noun. Almost all of these end in -ly, but there are some common ones that don't, such as
very and
quite. These words tend to be intensifiers, e. g.
The girl ate a very big pizza.
Article - a word put next to a noun in order to make a reference to it.
That book, this man, the wall, a friend. These are always really short words.
Sentence - a complete thought. A simple sentence is one complete thought. Compound and complex sentences have more than one complete thought.
She went to the store.
Conjunction - this is a connector word and I can only think of five of them:
and, but, or, for and nor.
And is an additive word,
but gives conditions (so does
for, usually),
or implies choices and
nor implies negative choices. Conjunctions are how you put together compound sentences.
Compound sentences are two simple sentences strung together with a comma (usually) and then a conjunction, e. g.
She went to the store, and her brother went to the movies. If you cut out the comma and the conjunction, and stuck a period in there instead, you'd have 2 perfectly good simple sentences. A
complex sentence uses a semicolon instead of the comma-conjunction combination, e. g.
She went to the store; her brother went to the movies.
Preposition - this is a word that indicates location, e. g.
up, down, under, above, beneath, beside, between.
See also:
http://en.wikipedia.org/wiki/Category:Parts_of_speech
I hope this helps.