Wiktionary
vb. (context archaic English) (form of second-person singular simple past can English)
Usage examples of "couldst".
I had foreknown, thou couldst not forebear to save a poor weakling, beset by human wolves.
And only when thou didst refuse, and that with such force that I knew thou couldst not be persuaded, did I seize thee.
Oh, didst thou think, Atene, that thou couldst hide the truth from the all-seeing Hesea of the Mountain?
I gladly, all of it, couldst thou but repay me with the boon of death to come.
I slew thee in yonder Place of Life, yes, in my madness I slew thee because thou wouldst not or couldst not understand the change that had come over me, and shrankest from my loveliness like a blind bat from the splendour of flame, hiding thy face in the tresses of her dusky hair--Why, what is it now, thou Oros?
Bill and Mushy betook ourselves to a place where we couldst get some real whiskey and not the stuff they make in them Scandinavian countries.
They was a decrepit punching bag, a horizontal bar and a lot of bar-bells, dumb-bells, kettle bells--in fact, all the lifting weights you couldst imagine.
All I couldst see was his glaring eyes, his big shoulders hunched and rocking as he hit--and a perfect whirlwind of big glove-covered clubs.
Yokohama than Mushy Hansen beat it down the waterfront to see if he couldst match me at some good fight club.
Before he couldst recover his balance, I tore into him like a wild man, forgetting everything except that I was Steve Costigan, the bully of the toughest ship afloat.
With the Old Man and that fake referee offa my mind, I couldst give all my thoughts to the battle.
He tried to get his legs under him, but a child couldst see he was done.
Vain of fugitive successes, O light-minded man, full of pleasure and of wealth, hast thou imagined that thou couldst suffice even to thyself?
But couldst thou not have done this better an thou hadst remained in thine own country?
Thou couldst but make thy creature dream of them, because thou canst but dream of them thyself.