Which of the following are words in which some letters do not correspond to their common sounds?

Irregular words are those in which some letters do not correspond to their common sounds, making them challenging for readers to decode using standard phonetic rules. These words often contain letter combinations or patterns that deviate from predictable phonetic principles, requiring memorization rather than reliance on decoding strategies. For example, "yacht," "said," and "was" feature spellings that do not sound as they might be pronounced using typical phonics rules, highlighting the irregularity in their sound-letter correspondence.

In contrast, decodable words, regular words, and sight words adhere to more predictable phonetic patterns or are taught based on recognition, making them less problematic in terms of sound-letter correspondence. Decodable and regular words typically follow phonics rules, while sight words are often high-frequency words that students learn to recognize by sight but may not necessarily fit phonetic patterns.