When Does the Sound of a Past Tense Verb Sound Like a "t"?

When does the sound of a past tense verb sound like a "t"?

It sounds like a "t" when the last sound of the base form of the verb in the present tense is "k," "f," "s," "p," "sh," and "ch."

Here are some examples:

"k": check, ask "f": laugh, cough "s": kiss, pass "p": tip, slap "sh": splash, push "ch": match, itch