What's the difference between diddest and didst?

Diddest

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Definition:

Example Sentences:

Didst

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Definition:

• () the 2d pers. sing. imp. of Do.

Example Sentences:

• (1) It's when Rosalind says to Celia: "O coz, coz, coz, my pretty little coz, that thou didst know how many fathom deep I am in love.