With other irregular verbs, all three forms are different.
It takes on different connotations when combined with other verbs.
These prefixes can also be used with other verbs to express 'to do something while coming this way'.
The first is with verbs of motion and indicates purpose.
Do also occurs with other verbs in both varieties of HE.
As mentioned above, the preterite form is only used with strong verbs.
With verbs of the movement it means "back and forth".
With fewer verbs, it indicates the beginning of and action.
Tense is also optional, and may be used with verbs or nouns.
Often used with verbs of being, emotion, capability, or conscience.