It's a bit tricky because the "ai" combination usually makes the "ay" sound (like in "plain" or "rain"). But in "plaid", it makes the short "a" sound, similar to the "a" in "cat" or "hat".
It's a bit tricky because the "ai" combination usually makes the "ay" sound (like in "plain" or "rain"). But in "plaid", it makes the short "a" sound, similar to the "a" in "cat" or "hat".