Is the sentence structure right?

It's okay, but starting the second sentence with a "Because" makes it informal.

Anonymous

How about:

 

"The other 95% are placed before completion of the training."

Fine, because you now have a main clause. There is nothing wrong with beginning a sentence with because, since or  as as long as you have a main clause as well. Otherwise, strictly speaking, you don't have a sentence since because, since and as are subordinate conjunctions, beginning subordinate clauses. A subordinate clause cannot constitute a sentence.

An example of a sentence beginning with these conjuntions:

Because/since/as I didn't know his number, I couldn't call him. = I couldn't call him because/since/as I didn't know his number.

In informal style grammatical considerations are often cast aside in all languages, and using because without a main clause is very common:

"Why didn't you call him?"

"Because I didn't know his number."

 Since and as would be just as "grammatical" as because in the above sentence but they just aren't used.

CB