Both the SAT and ACT test grammar; the SAT in the Multiple Choice Writing Section, and the ACT in the English Test. A thorough knowledge of English grammar is also necessary if you want a top score on the essay section of either exam. In this post we’ll discuss one grammar rule that, while not directly tested, is important to know in order to understand how many other grammar rules work: what is the difference between a clause and a phrase?
In a nutshell, a clause always has a subject and a verb; a phrase does not. All complete sentences must contain at least one independent clause. An independent clause is a clause that could potentially stand alone as a sentence. For example:
This is an independent clause: it has a subject (Pigs) and a verb (fly) and forms a complete thought that can stand on its own. There are also dependent clauses, which cannot stand alone for various reasons. Consider, for instance:
Unless this is a question, it would not make sense on its own, because we don’t know who is flying. “Who” is a relative pronoun: that means that it has to refer back to someone in order to make sense. Consider this version:
Superman is a superhero who flies.
Now, the dependent clause “who flies” makes sense because it is attached to an independent clause (Superman is a superhero) that tells us whom the word “who” refers to (Superman).
A phrase, on the other hand, is any group of words that does not form a complete clause. Usually, phrases function as distinct grammatical units. Consider for example a very common type of phrase: the prepositional phrase. Prepositional phrases always consist of a preposition followed by a noun which functions as its object:
Prepositional phrase = preposition + noun (object)
through the clouds
Here, “through” is the preposition and “the clouds” is the object of that preposition. Note that the phrase “though the clouds” does not make sense as a sentence on its own. It needs to be part of an independent clause:
Why is this important? Consider the following sentence:
The man who flies in the air by planes with steel wings are very strong.
There is something wrong with this sentence. What is very strong? The wings? Or the man? The man, of course, because the man is the subject of the independent clause. Because “the man” is a singular noun, the plural verb “are” should be changed to the singular version “is.” Notice that the plural “are” does agree with the plural “wings”; however, the “wings” are the object of the preposition “with,” and the object of a preposition can never be the subject of a sentence. This is a common trick the test makers use to try to confuse students: they separate the subject of a clause from its verb with intervening wastes of prepositional phrases and hope that by the time you get to the verb you will have forgotten what the subject was.
One of the best things you can do on any grammar question is start by identifying the subject and verb of each clause in the sentence. Even if there aren’t any subject/verb agreement errors, you will have identified the essential structure of the sentence and will be well prepared to find other errors after that.
Remember, if you want extra help studying for the SAT or ACT, you can always study with experts like me at Test Masters. Until next time, keep studying!