The first rule regarding sentences is that a sentence must contain a complete thought and must be able to stand by itself and make sense. A fragment is an incomplete sentence. It isn’t an independent clause, and it does not make a complete thought by itself.
A clause is simply a subject and verb that go together. An independent clause is a subject and a verb that can stand alone and make sense.
Clauses can be very short:
FCA reviewed the policy.
Here, FCA is the subject and reviewed is the verb.
Or quite long:
The growth in long-term real estate loans reflects the growing propensity for lenders to use farm land as collateral for all loans, including those used for purposes other than the purchase of farm land, during the continued upsurge in farmland values.
Here, growth is the subject and reflects is the verb.
A fragment, by contrast, lacks one of the required elements of a subject and a verb:
Improvement in the capital ratio from earnings.
Here, improvement is the subject and the verb is missing.
Another situation that results in an incomplete sentence is when there is a subject and a verb but the clause is introduced with a word like although, when, because, or while. Here are examples of fragments that open with subordinate adverbs:
While quality indicators such as delinquency and loss remained low.
Although the goals and objectives emphasized strengthening capital and earnings levels and demonstrated the board’s commitment to maintain financial strength for ongoing profitability.
Neither of these is a complete thought and therefore cannot be considered a complete sentence. Although each of the examples above contains a clause (a group of words with a subject + a verb), they are dependent clauses—meaning they must depend on another clause to complete the thought. For a clause to be able to stand alone and be a fully functioning sentence, it needs to have a subject and verb and constitute a complete thought.