One word formed with two hyphenated words and used to describe a noun.
Adjectives describe, quantify, or identify pronouns and nouns. They also answer the following questions: What kind? How many? How much? Which one?
Descriptions about "What kind?" add detail about the qualities of the noun or pronoun being described. This ranges from details regarding physical characteristics to emotional states. Here are some examples: the yellow dress, the sad clown, the smart pupil.
Descriptions answering "How many?" and "How much?" specify the amount of whatever noun or pronoun you are modifying. Quantifying adjectives can be specific (ten candles, three hundred pages) or general (several minutes, a fewpeople, some candy).
Descriptions answering "Which one?" confirm exactly which object the writer is referring to. Examples include phrases such as "that novel," "this writer," or "those students." Most adjectives that serve this purpose are called determiners or demonstrative pronouns.
In some situations, two adjectives may be used to describe a noun. Sometimes these two adjectives remain separate, as two distinctive words describing the noun. But other times, the adjectives combine to become one adjective joined by a hyphen.
The phrase a heavy metal detector refers to a metal detector that is heavy in weight. Heavy and metal are separate adjectives describing the detector in this situation.
The phrase a heavy-metal detector refers to a detector of heavy metals. Heavy-metal is the compound adjective describing the detector.
As you can see, the hyphen completely changes the meaning of the phrase by combining two words into one. Here's another example:
The phrase man eating shark refers to a man who is eating a shark.
The phrase man-eating shark refers to a shark that eats men.
Adjectives for Comparison
Adjectives are also used to compare items:
This year's graduating class was smaller than last year's class.
This book is the best one we've read so far.
The standard form for using adjectives for comparison is to add -er to the end of an adjective being used to compare two items (brighter, cooler) and -est to the end of an adjective used to compare more than two items (brightest, coolest). However, some adjectives—for example, ones that are three or more syllables—like beautiful are changed to say "more beautiful" and "most beautiful" rather than adding these endings.
Pronouns as Adjectives
Sometimes, pronouns can be used as adjectives. In addition to demonstrative pronouns, possessive pronouns like "his" or "their" can also identify specific objects within a set. For example:
Which car should we drive? We should drive her car.
Whose house is closest? Your house is closest.
Prepositional Phrases as Adjectival Phrases
Prepositional phrases can act as adjectives, normally modifying the noun that precedes them.
Which books should we read? The books on the curriculum.
Whose stories did we listen to in class? Those of the teacher.
Lastly, in addition to single words, you can use adjectival phrases. These are phrases that begin with an adjective but then have a noun that adds further detail, such as "full of toys" instead of just "full." They are most frequently used as a modifier placed right after a noun or as a predicate to a verb. For example, you could say "The child loved his bin full of toys," or "That bin is full of toys."