One of our newsletter subscribers wrote to ask us which phrase—”the reason is because” or “the reason is that”—is correct. Here are two examples of those constructions in a sentence:

  1. The reason we were late is because there was an accident on Interstate 26.
  2. The reason we were late is that there was an accident on Interstate 26.

The better choice is sentence 2.

Linking Verbs Link to Nouns, Pronouns, and Adjectives

Is is a linking verb. In most cases the subject of such a verb will be “linked” to a word that either describes the subject (an adjective) or renames it (a noun or pronoun or something functioning as a noun, such as a gerund or a noun clause). We call such words “subject complements” because they complete or “flesh out” the subject.

For example, in the sentence “She is the president,” the word president is a subject complement (a predicate noun in this case). It renames the subject she.

In the sentence “She is nice,” the word “nice” is also a subject complement (a predicate adjective in this case). It describes the subject she.

In a sentence with a linking verb, the subject complement will be either an adjective or a noun (or a phrase or clause that is functioning as one of these two parts of speech), but a subject complement can never be an adverb. (It is possible, of course, for an adverb to follow a linking verb, as in the sentence “She is here.” But instead of complementing the subject, the adverb here modifies the linking verb, answering the question “Where is she?”)

What about Our Sentence?

Now, let’s consider our opening sentences:

The first sentence won’t work because the subject (reason) is being linked to a clause that functions as an adverb: “because there was an accident on Interstate 26.”

One trick for remembering which construction is appropriate is to think of the words reason and because as creating a redundancy, saying in effect “the reason is the reason.”

Another of our articles addresses the difference between bad and badly. We avoid saying “She feels badly about his accident” because feel in this construction is a linking verb, just like is in the opening sentences of this discussion. As we have noted, linking verbs most often connect subjects to nouns or adjectives (in this case, the adjective bad, not the adverb badly). Thus, the correct expression is “She feels bad about his accident.”

TEST YOURSELF

Three of the following four sentences are preferable to the fourth.  Can you spot the weak sentence?

  1. The reason for the recent increase in temperatures is the low-pressure system stalled off the coast.
  2. The temperatures have increased recently because a low-pressure system is stalled off the coast.
  3. The reason temperatures have increased recently is because a low-pressure system has stalled off the coast.
  4. The reason temperatures have increased recently is that a low-pressure system has stalled off the coast.

ANSWERS

  1. This construction is fine: The subject (reason) is appropriately linked (by the linking verb is) to the noun phrase “the low-pressure system stalled off the coast.”
  2. This one is also fine: The adverb clause “because a low-pressure system is stalled off the coast” appropriately modifies the verb “have increased” (which is an action verb, not a linking verb).
  3. The syntax in the third sentence is problematic: In this sentence, the subject (reason) is inappropriately linked (by the linking verb is) to the adverb clause “because a low-pressure system has stalled off the coast.”
  4. This sentence is fine: The subject (reason) is appropriately linked (by the linking verb is) to the noun clause “that a low-pressure system has stalled off the coast.”

©2003 Get It Write. Revised 2018.