R - S

Sentence Fragment

When a group of words forms a sentence, it expresses a complete thought. But when a group of words, such as a clause or phrase, that does not express a complete thought, it is a sentence fragment. A sentence fragment comes about when something – a subject, a verb or both – is missing in it. The presence of a subject and a verb can still give rise to a sentence fragment.

Examples:

A sentence fragment happens due to the following:
(1) A dependent clause used as a sentence: I'll feed the dogs. After I have finished with this.
(2) A phrase incorrectly stands on its own: Wishing you a safe journey.
(3) A verb used incorrectly: No, thanks. I drunk enough.
(4) An -ing ending verb must follow a helping verb: He coming to join us for a drink.
Correction:
(1) I'll feed the dogs after I have finished with this.
(2) I wish you a safe journey.
(3) No, thanks. I have drunk enough.
(4) He is coming to join us for a drink.

A simple sentence has one independent clause with a subject and a verb. A sentence having a compound subject or a compound verb is still a simple sentence. A simple sentence can have a modifier such as an adjective or adverb. More on simple sentence.

Examples:

That bird is a penguin. / That black and white bird is a penguin. (One subject + one verb)
Tom and Jerry are my favorite cat and mouse. (Compound subject uses one plural verb.)
She bit and scratched her husband in a fight. (One subject + compound verb)

Subject Complement

A subject complement forms a part of a predicate of a sentence. It can be divided into: Predicate nominative or predicate noun is always a single noun or a noun phrase, or a pronoun. Predicate adjective is an adjective modifying the subject. Both predicate noun and predicate adjective follow a linking verb and rename or describe the subject of a sentence.

Examples:

The following examples show the predicate nouns in bold.

In my dream last night¸ the scarecrow became a human.
We remained bitter enemies after a big fight.
(The predicate nominative/predicate noun and the subject must be the same person: scarecrow = human; we = enemies. The linking verbs are became and remained.)

Examples:

The following examples show the predicate adjectives in bold.

The little hair left on his head is curly.
We could see that grandpa grew more childish and happier every day.
(The linking verbs are was and grew.)