I’m pretty sure that the second statement in that sentence is a sentence fragment.

In the sentence we do not know WHAT the moment is(without the use of other sentences around this one), when in fact “this”describes what the moment is. I hope that wasn’t confusing. You’re missing a subject and a verb to go with your direct object. A complete sentence should be able to stand alone without the help of other sentences.

Look at the first part of the sentence:

“The moment I had been waiting for”

It doesn’t really stand alone does it?

If you want to turn it into a complete sentence without too many commas, you might want to try these alternatives:

-This was it! It was the moment I had been waiting for, but not necessarily looking foward to, all day.

-This was it! I had been waiting for this moment, but not necessarily looking foward to it, all day.

Try rewriting the sentence in as many ways as you can possible think and choose the one that has the best flow and use of punctuation.

Extra tips for identifying sentence fragments:

1) Turn the statement into a true or false question by adding “wasn’t it?” or “didn’t it?” at the end. Then ask yourself, “can I answer this question?”

2) Ask yourself whether the statement would convey a complete thought by itself, without the sentences surrounding it.

Also keep in mind that not all sentence fragments are prohibited. Sentence fragments are acceptable in some types of writing, for stylistic or emphatic purposes. They are used in creative writing, poetry, advertising and journalism.

If you don’t know whether or not sentence fragments are accepted for anything you are writing (and turning in), you should always make it a complete sentence.

The second one is more correct, because “the moment I had been waiting for, but not necessarily looking foward to, all day” doesn’t stand alone as a sentence. It is a fragment. Many writers use fragments and call it artistic license (or don’t know any better), but if you want to be grammatically correct it should be one sentence. It’s sad that some students don’t pay more attention to grammar in school.

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The answerer below has some good advice on grammar, but I’d suggest this alternative: “This was the moment I had been waiting for, but not necessarily looking foward to, all day!” It avoids that awkward break between phrases. Even if “that” is more grammatically correct for the past tense in general usage, I think artistic license applies here because “this” conveys a sense of immediacy that is more involving for the reader and more appropriate to the first-person narrative approach.

“The moment I had been waiting for, but not necessarily looking foward to, all day” is THE fragment.

And “this was it” is grammatically wrong even though it is a complete sentence. It shoud either be “this is it” or “that was it.”

So you could write: “That was it! It was the moment I had been waiting for, but not necessarily looking foward to, all day.”

Or, “This is it — the moment I had been waiting for, but not necessarily looking foward to, all day.” Just be sure you use the dash and not the hyphen.

I decided to use “this is it” here instead of “that was it” because the present tense imparts a bigger impact and is still grammatically correct. But in the first version I had to use the past (“that was it”) to agree with the sentence that was to follow.

The moment one is a fraction. To recognize why, you have to realize what clauses are. A clause is most of the time a sort of word. There are 2 clauses: unbiased and subordinate. Independent clauses have a area and predicate, however subordinatclausess do not. Independent clause can stand on my own as a sentence. For ex. The blouse is blue. Subordinate clauses are not able to stand on my own within the sentence. They want some thing to entire them. ex. If the blouse is from Wal-Mart. Putting an unbiased clause and subordinate clause in combination creates a sentence. ex. If the blouse is from Wal-MArt, the blouse is blue. A trace for locating subordinate clauses is that begin with the phrase “if” plenty. Also, Subordinate clauses are constantly separated from unbiased clauses with a comma.

The first one because “This is it!” makes one statement, if you put a comma after it then its a run on sentence.

This was it is right. This was it, the moment I have been waiting for it wrong. This was it is one idea. I have been waiting for it is another idea.