You have already learned that these parts _alone_, sometimes make a
complete structure; but we are about to show you that they are often used
as the foundation of a structure, which is completed by adding _other_
parts.

I hold in my hand several pieces of metal, with letters and other
characters stamped on them. What do you say I have in my hand? +P+.--Money.
+T.--+Yes. What other word can you use? +P.--+_Coin_. +T.--+Yes. I will
write on the board this sentence: _Coin is stamped_.

The subject _coin_ is a general name for all such pieces of metal. I will
write the word _the_ before this sentence. _The coin is stamped_. I have
now made an assertion about one particular coin, so the meaning of the
subject is limited by joining the word _the_.

I can again limit the meaning of the subject by putting the word _a_ before
it. The assertion is now about one coin, but no particular one. I point to
the piece near me and say, _This coin is stamped_. I point to the one
farther from me and say, _That coin is stamped_.

When words are joined to the subject to limit its meaning, we say that the
subject is _modified_.

The words _the, a, this_, and _that_ modify the subject by limiting the
word to one coin, or to one particular coin.

We can modify the subject by joining some word which will tell what _kind_
of coin is meant.

Here is a coin dated 18--. We can say, _The new coin is stamped_. Here the