All words used in dictation should have been previously taught in spelling analysis but they may have been taught in that level or any level lower than they are working in. For example, if you are completing Level B, then Level B and Level A spelling analysis words may be used for dictation. However, if you are completing Level A, then only Level A words previously taught will be used.
If your student misses elements of words in dictation phrases/sentences, we recommend using those words in some games for review, but also some other words that have the same elements. For example, if they missed that "echoes" is spelled with ES, maybe use "echoes" and "heroes" in a game for review. Or if they missed the EA in "threatens," then pick some other EA words to throw into a review game along with "threatens."
However, if they are missing sounds completely, for example, did not add the S to the end of "threatens" or left out the /r/. Then I would play some phonemic awareness games to help your student hear every sound in the word.
Spelling is a great window into a student's reading. If a student consistently misses a sound, they may be having trouble hearing that sound in words. We strengthen these skills through phonemic awareness games. More about phonemic awareness here.
If you need some game ideas, please check out our free LOE Literacy Games Course.