The verb exercise is a regular verb. Exercise has a consonant and a silent e at the end, so you should edd just d to the end. And ed is pronounced [id] in this verb.

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Is this explanation correct? If there are errors, correct them, please.

2 answers

Change "edd" to "add" -- and the sound produced is [d], not [id] which implies an additional syllable. The whole word when pronounced in past tense is [ex-er-sizd].

Let me know if this doesn't make sense.

=)
Thank you for your correction. I will post corrected sentence.

The verb exercise is a regular verb. Exercise has a consonant and a silent e at the end, so you should add just d to the end. And ed is pronounced [d] in this verb.