Should US President Donald Trump thumb through a dictionary before putting his thumb to work on tweets?

Trump confused "t-o" and "t-o-o" during a series of tweets on Thursday (Friday NZ Time), getting it right after three tries. He also replaced "t-h-e-i-r" with the correct "t-h-e-r-e" in the same two-part tweet.

At the weekend, Trump was tripped up by "h-e-e-l" when he meant to write "h-e-a-l" in comments about duelling rallies in Boston.

And, of course, there's Trump's famous "covfefe" tweet, sent in late May.

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In a succession of posts on Thursday (Friday NZT) about his tone in three speeches this week, Trump twice said "T-o bad the Dems have no one who can change tunes!" before changing to the correct "T-o-o bad the Dems have no one who can change tunes!" In the first part of the two-part tweet, Trump used "t-h-e-i-r" before correcting to "t-h-e-r-e".

..(enthusiastic, dynamic and fun) and the American Legion - V.A. (respectful and strong). Too bad the Dems have no one who can change tones! — Donald J. Trump (@realDonaldTrump) August 24, 2017

Trump's presidential misspelling on Twitter dates to his first full day in office, when he described himself as "h-o-n-e-r-e-d" to serve as the 45th US president.

The New Yorker and former businessman isn't the first American politician to take bad spelling public.

A whopper occurred in 1992 when US Vice President Dan Quayle relied on a faulty flash card and erroneously instructed a New Jersey sixth-grader to put an "E" at the end of "potato".

Now, back to "covfefe".

Trump left the world hanging just after 11pm on May 31 (local time) when he tweeted: "Despite the constant negative press covfefe". The tweet tantalised the Twittersphere until Trump completed his thought about six hours later. "Who can figure out the true meaning of 'covfefe'??? Enjoy!" he wrote.

The White House never fully explained what Trump was getting at.

Questioned about the mysterious tweet, then-press secretary Sean Spicer said "the president and a small group of people know exactly what he meant".

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