Final answer:
The Spelling command does not specifically complete columns of month or day names; this appears to be a misunderstanding of word processing or spreadsheet functionalities. True spelling exercises often involve recognizing and applying spelling patterns and rules.
Step-by-step explanation:
The Spelling command does not specifically complete columns of month or day names. This looks like a task related to a word processing or spreadsheet software feature, but it's not clear from the context provided. Typically, programs like Microsoft Word or Excel have functionalities to fill in dates, but the way you describe it as a Spelling command seems incorrect for completing columns of dates. For a spelling-focused task, you're more likely to encounter exercises that help you practice spelling patterns and rules, such as determining when to use single or double letters in words that sound similar (for example, little vs. settle). Sorting words into groups or writing them backwards helps reinforce these patterns.