This week, we look at a pair of commonly confused homophones: principal and principle.

This week marks our 100th original episode, as well as the 2nd anniversary of Grammar Grater. We're celebrating the occasion by presenting a "clip show" of some of our favorite moments from the past two years.

We examine another pair of words that can cause confusion: amuse and bemuse.

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This week, we continue our two-part look at the issue of trademarks in writing.