Ok, here’s the deal. Dive is a regular verb, and a regular verb makes its past tense form by adding –ed to the end (or just –d if there’s already an –e at the end of the word). The past tense of dive, then, is dived.
Dove has become widely used as the past tense of dive, and it is frequently listed in dictionaries as an alternative to dived; however, many experts, grammarians—-and English teachers handing out the latest grammar quiz—-still call it colloquial, non-standard, or even substandard. (I, myself, prefer to cut to the chase and call it wrong.)
I can’t say that I understand the logic of taking a verb that has been classified as regular and re-classifying it as regular and irregular. (As we all know, all regular verbs follow the same pattern of conjugation, but each irregular verb has its own pattern that must be memorized.) The evolution of dove as an alternative past tense of dive is obviously the result of an oft-repeated grammar error that went for too long without being corrected.
If you want to be certain of using the correct conjugation, stick with the traditional dived for the past tense of dive.
- I dived in and did the necessary work.
- We dived from the 25-meter board.
Think of the past tense of words such as skydive; we say skydived, not skydove.
The past participle of dive is dived as well, as in I have never dived from that height before or She’s dived off that cliff many times.