Second-person singular simple present form of write(verb)
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Use "writest" in a sentence
"E'en though thou like it not, this is what the gods decree; but thou, after letting thy taper spread its light abroad, writest the letter which is still in thy hands and then erasest the same words again, sealing and re-opening the scroll, then flinging the tablet to the ground with floods of tears and leaving nothing undone in thy aimless behaviour to stamp thee mad."
"To his Secretary he said, ‘Thou art the controller of my wit: so do thou watch over me in what thou writest for me and from me.’"
"Though thou hadst not so good an invention as he to whom thou writest, thou hadst as active an heart for mischief, as ever I met with in man."