Which of the following words violates the sonority sequencing principle?

• A. spot
• B. sweep
• C. brown
• D. past

Answer: (A)

The main idea here is the Sonority Sequencing Principle: within a syllable, sounds should rise in sonority toward the vowel in the onset, and fall away from the vowel in the coda. Sonority estimates from lowest to highest roughly go stops, then fricatives, then nasals, then approximants (glides and vowels are the most sonorous).

In the onset of the word with the cluster sp, the first sound is s, a fricative, and the second is p, a stop. Since a fricative has more sonority than a stop, the sequence from the onset toward the vowel actually decreases in sonority, which breaks the pattern the principle expects. That’s why it violates the rule.

The other words fit the pattern: sweep has an onset sw where a fricative is followed by an approximant, rising in sonority toward the vowel; brown has an onset br where a stop is followed by an approximant, also rising toward the vowel; past has a simple onset and a coda st where the sonority falls away from the vowel, which is allowed.