Language Essentials for Teachers of Reading and Spelling (LETRS) Unit 2 Practice Test

The most likely phonological error when a student writes "vis" instead of "this" relates to the confusion between two different voiced fricatives. In the case of "this," the initial sound is a voiced dental fricative /ð/, while in "vis," the initial sound is a voiced labiodental fricative /v/. Both sounds are voicing fricatives, which means that the vocal cords vibrate during their articulation. This aligns with the option indicating confusion between voiced fricatives, where the student may have substituted one fricative sound for another that shares the same voicing feature.

The other options do not align with this error. Substituting a nasal sound for a fricative involves different types of sounds altogether, and substituting a glide sound for a fricative does not pertain to the sounds in question. Additionally, substituting an unvoiced fricative for a voiced fricative would indicate that a sound like /f/ (unvoiced) was replaced with a voiced counterpart, which does not apply here since both "this" and "vis" begin with voiced fricatives. Therefore, the specific confusion between the two voiced fricatives provides the necessary context