From here on out 'here' will be ここ, 'there' will be そこ, and 'over there' will be あそこ, but don't forget that the words are in reference to the speaker and who is being spoken to.

Now we can instert our location words into the 'X はY です' patterns.

えんぴつは　どこ　ですか。

Where is the pencil?

えんぴつは　あそこ　です。

The pencil is over there.

One can also describe objects given their location. If you want to indicate a pencil you are holding or one near to you 'this pencil' (as opposed to a pen near someone else) you say このえんぴつ. If you are indicating a pencil near the person you are speaking to (and not yourself) you say そのえんぴつ. And finally, if you are indicating a pencil away from both of you, you say あのえんぴつ. To ask which pencil (out of more than one indicated pencil), you say どのえんぴつ.

NOTE: この, その, あの, and どの must be followed by a noun that they are describing. They cannot stand alone.

this ___ (next to me)
that ___ (next to you)
that ___ over there (away from us)
which ___

Examples:

この　いぬは　わたしの　です。

This dog is mine.

あの　ひとは　だれ　ですか。

Who is that person over there?

その　えんぴつは　だれの　ですか。

Whose pencil is that?

To indicate ownership of an object, the possessive の particle is used.

Examples:

だれの　いぬ　ですか。
わたしの　いぬ　です。

だれの　ねこ　ですか。
わたしの　です。

だれの　ねこ　ですか。
スザンさんの　ねこ　です。

あなたの　ですか。
いいえ、マイクさんの　です。

Examples:

これは　なん　ですか。

What is this?

この
その
あの
どの

これ
それ
あれ
どれ

ほん
えんぴつ
ひと

this ___ (next to me)
that ___ (next to you)
that ___ over there (away from us)
which ___

this (next to me)
that (next to you)
that over there (away from us)
which

book
pencil
person