Wow, you're really in the messy bits of English now.

Let's look at these two sentences:

1. Despite the fact that tourism develops fast, it has created many problems.

2. Watching TV results in the problem that children cannot concentrate on their studies.

The first sentence sounds correct (although it slightly misuses the word "despite"), but the second sentence definitely does not. Unfortunately, as far as I know, the first sentence is not an example of an appositive clause, so that makes things more confusing for you.

An appositive clause is a way to combine two sentences. In the first sentence, you describe what a noun is. In the second, you say what the noun does. The easiest way to form a correct appositive clause is to start with the two sentences. For example:

Clifford is a big dog. Clifford ran across the yard.

You may then simply remove the subject, the word "is", and place the predicate of the first sentence after the subject of the second, surrounded by commas. For example:

Clifford, a big dog, ran across the yard.

Now, let's break apart the second sentence:

Watching TV causes problems. Children cannot concentrate on their studies.

These sentences are related, but since they do not have the same subject, an appositive clause cannot be used.

Now let's break apart the first sentence:

Tourism grows very fast. Tourism causes many problems.

Note that we are using verbs in both of these sentences. We do not state what tourism is. Therefore, we have to use phrases that can compare verbs. "Despite the fact" is a phrase that can be used. It takes this form: [A is happening] despite the fact that [B is happening].

Tourism grows very fast despite the fact that tourism causes many problems.

Now, if you want, you can move the second sentence before the first:

Despite the fact tourism causes many problems, it grows very fast.

Sorry, there was a small typo in my last sentence. It should have read:

Despite the fact that tourism causes many problems, it grows very fast.

Even easier, if you can get rid the noun the appositive clause trying to modify and if the sentence still makes the original sense, it is INDEED an appositive clause.

I hate the fact that I have to takes my shoes off before entering the house. --> I hate that I have to take my shoes off before entering the house. --> original meaning intact --> Appositive clause

I hate the fact that we wrote down on the paper. --> I hate that we wrote down on paper. --> original meaning changed --> Relative clause

"Watching TV results in the problem that children cannot concentrate on their studies." Here, "that children cannot concentrate on their studies" is an appositive clause in that it modifies the "problem". The appositive clause can stand on its own as a separate sentence. Another word, you can say "Watching TV results in a problem. The problem is that children cannot concentrate on their studies." Therefore, there is indeed an appositive clause here.

To make the relative (not appositive), you can say "Watching TV results in the problem that we face today." Here, "that we face today" does not modify the "problem" but rather "problem" is the object of the verb "face". Another word, you cannot separate this relative clause into its own sentence and say "Watching TV results in the problem. We face [what?] today." Therefore, there is no appositive clause here.

My tip is that for as long as you can separate the clause out and it modifies the noun/group of nouns, it is an appositive clause. No need to memorize anything. :-)

I hope that helps.