How can we know to what class, or part of speech, any word belongs?  By learning the definitions of the ten parts of speech, and then observing how the word is written, and in what sense it is used.  It is necessary also to observe, so far as we can, with what other words each particular one is capable of making sense.

1.  Is it easy to distinguish an ARTICLE?  If not always easy, it is generally so:  the, an, and a, are the only English words called articles, and these are rarely any thing else.  Because an and a have the same import, and are supposed to have the same origin, the articles are commonly reckoned two, but some count them as three.

2.  How can we distinguish a NOUN?  By means of the article before it, if there is one; as, the house, an apple, a book; or, by adding it to the phrase, “I mentioned;” as, “I mentioned peace;”—­“I mentioned war;”—­“I mentioned slumber.”  Any word which thus makes complete sense, is, in that sense, a noun; because a noun is the name of any thing which can thus be mentioned by a name.  Of English nouns, there are said to be as many as twenty-five or thirty thousand.

3.  How can we distinguish an ADJECTIVE?  By putting a noun after it, to see if the phrase will be sense.  The noun thing, or its plural things, will suit almost any adjective; as, A good thing—­A bad thing—­A little thing—­A great thing—­Few things—­Many things—­Some things—­Fifty things.  Of adjectives, there are perhaps nine or ten thousand.

4.  How can we distinguish a PRONOUN?  By observing that its noun repeated makes the same sense.  Thus, the example of the pronoun above, “The boy loves his book; he has long lessons, and he learns them well,”—­very clearly means, “The boy loves the boy’s book; the boy has long lessons, and the boy learns those lessons well.”  Here then, by a disagreeable repetition of two nouns, we have the same sense without any pronoun; but it is obvious that the pronouns form a better mode of expression, because they prevent this awkward repetition.  The different pronouns in English are twenty-four; and their variations in declension are thirty-two:  so that the number of words of this class, is fifty-six.

5.  How can we distinguish a VERB?  By observing that it is usually the principal word in the sentence, and that without it there would be no assertion.  It is the word which expresses what is affirmed or said of the person or thing mentioned; as, “Jesus wept.”—­“Felix trembled.”—­“The just shall live by faith.”  It will make sense when inflected with the pronouns; as, I write, thou writ’st, he writes; we write, you write, they write.—­I walk, thou walkst, he walks; we walk, you walk, they walk.  Of English verbs, some recent grammarians compute the number at eight thousand; others formerly reckoned them to be no more than four thousand three hundred.[131]