At a school where I worked we had a test called Woodcock-Munoz. The test was to place new English learners into the appropriate level. One section was an anology section where a student is presented with a pairing of words that have a certain relationship and they must respond with a word that has a similar relationship. For example, "man is to grandfather, as woman is to grandmother." One question was "cut is to hair, as mow is to _____." One student said, "cow!"
The student had confused "mow" with "moo."