The last set of ko-so-a-do words are この (kono), その (sono), あの (ano), and どの (dono). These words also mean "this" and "that," like これ, それ, あれ, and どれ. However, これ, それ, あれ, and どれ refers to an object as "this thing" and "that thing" whereas この, その, あの, and どのare followed by a noun to mean "this (noun)" and "that (noun)." Just remember: the -れ words are always by themselves and the -の words always have a noun.
これはえんぴつです。 (kore wa enpitsu desu)
This is a pencil.
このえんぴつは。。。 (kono enpitsu wa)
This pencil is...
This is the difference between これ and この. この is followed by a noun to make it specific (this pencil), and これ by itself refers to an object (this object near me).
So following the ko-so-a-do pattern we've learned before, here are the definitions of この, その, あの, and どの:
この + NOUN = this NOUN (NOUN is near the speaker)
その + NOUN = that NOUN (NOUN is near the listener)
あの + NOUN = that NOUN (NOUN far from both speaker and listener)
どの + NOUN = which NOUN (question word)
Like どれ, どの also means "which," the difference being that どの needs a noun after it. Also, どの + NOUN cannot have the particle は after it and must use が.
どのえんぴつがやすいですか。 (dono enpitsu ga takai desu ka)
Which pencil is cheap?
どれがやすいですか。 (dore ga yasui desu ka)
Which one is cheap?
And with this, we are done with our ko-so-a-do words!