Basic writing concepts: parts of speech and elementary sentence structure. These concepts are described with examples below.
Parts of speech describe the roles words play in sentences.
Nouns name persons, places, things, or ideas, and they act as subjects and objects in sentences. Concrete nouns that refer to tangible objects such as vertebrates, genes, and DNA; and abstract nouns that refer to intangible ideas, emotions, or qualities such as understanding, interpretation, and prediction. Nouns are often introduced by articles: a, an, or the.
Scientists have studied the arms of spiral galaxies.
The nouns in this example are all concrete: scientists, arms, and galaxies. Arms is introduced by the article the.
Pronouns substitute for nouns. Some common pronouns are: I, you, we, it, they, this, that, those, who, which, and what.
They have studied them to determine the origin of spiral structure.
The pronoun they substitutes for the noun scientists in the previous example, while the pronoun them substitutes for the noun arms.
Adjectives describe or modify nouns or pronouns.
Many scientists have studied the beautiful arms of spiral galaxies.
The adjective many modifies scientists , beautiful modifies arms , and spiral modifies galaxies.
Verbs show action or state of being.
Many scientists have studied the beautiful arms of spiral galaxies.
The verb have studied describes the action.
Verbals look like verbs but function as adjectives, adverbs, or nouns.
The beautiful arms of spiral galaxies, outlined by luminous young stars, have been the focus of many studies.
In this sentence, have been is the verb. Outlined is a verbal that comes from the verb outline , but it functions as an adjective modifying the noun arms.
Adverbs modify verbs, adjectives, other adverbs, or whole sentences. They limit or define those parts of speech by answering the questions when ? how ? where ? how often ? and to what extent ?
We can identify the link between density wave acceleration of molecular clouds and the subsequent birth of stars most easily and unambiguously in galaxies external to our own.
The adverbs easily and unambiguously modify the verb can identify . Another adverb, most , modifies the adverb easily.
Most prepositions show position in space and time. Examples are: in , under , above , below , at , after, before, until , for , with , by , and on . However, a few common prepositions do not, such as of , as , and like .
Molecular clouds spend a large fraction of their time within the arms of spiral galaxies.
Conjunctions connect parts of sentences or entire sentences. Some common conjunctions are: and , but , or , nor , for , yet , so , however , consequently , therefore , and because.
Many scientists have studied the beautiful arms of spiral galaxies outlined by luminous young stars, but the origin of spiral structure and the trigger for star formation remains unclear.
Sentence structure refers to the way sentences are formed from words, phrases, and clauses.
The main action word in a sentence is the verb , and a good way to start deciphering sentence structure is by finding it.
Many shorebirds deplete the prey.
The verb is deplete, and it describes the action.
The subject is what you write your sentence about . Asking “who?” or “what?” in front of the verb, usually gives you the subject.
Many shorebirds deplete the prey.
The verb is deplete. Who or what depletes? The answer is shorebirds , the subject.
A sentence may or may not have an object — a noun that receives the action of the verb. In most cases, asking “who?” or “what?” after the verb gives you the object (circled below)(prey).
Many shorebirds deplete the prey.
Many shorebirds deplete what? The answer is prey, the object.
In the following example, the sentence has no object.
The shorebirds flew.
A clause is a group of words with a subject and a verb. There are two kinds of clauses: independent and dependent. Two or more clauses often make up a single sentence.
An independent clause has both subject and verb and can stand alone because it makes a complete statement. The simplest sentence is an independent clause.
When shorebirds deplete the prey in a small area, the flock must move to a fresh site.
The independent clause is the part of the sentence that can stand alone, the flock must move to a fresh site. It contains the verb must move and the subject flock and makes a complete statement.
A dependent clause has both subject and verb but cannot stand alone; it depends on an independent clause to make a complete statement.
When shorebirds deplete the prey in a small area , the flock must move to a fresh site.
The dependent clause is When shorebirds deplete the prey in a small area.
Because the clause begins with the dependent word when, it does not make a complete statement and cannot stand alone even though it contains the verb deplete and the subject shorebirds.
Here is a list of the common words that begin dependent clauses:
after since whereas
although so that wherever
as than whether
because though whichever
as if that which
before unless while
even if until who
even though what whom
ever since whatever whose
how when why
if whenever where
Phrases are groups of related words without subjects and verbs. They can function in sentences as subjects, modifiers, or objects.
A verbal phrase consists of a verbal and the words associated with it, shown in brackets in the following sentence.
Many shorebirds (feeding in a small area) deplete the prey.
The verbal phrase, feeding in a small area , functions as an adjective describing the shorebirds. Feeding is the verbal followed by the prepositional phrase in a small area.
A prepositional phrase consists of a preposition, an object, and any modifiers, shown in parentheses in the sentence below.
Many shorebirds (in a small area) deplete the prey.
The prepositional phrase, in a small area , describes the shorebirds’ position. In is the preposition, area is the object of the preposition, and small modifies area.