Does Learned Have an Apostrophe?

Because basically either form is correct. I learned – ed – or I learnt to drive a truck in the army. Either one is correct. But how can this be?

Which is correct Learnt or learned?

Learnt and learned are both used as the past participle and past tense of the verb to learn. Learned is the generally accepted spelling in the United States and Canada, while the rest of the English-speaking world seems to prefer learnt. Learn more about the details of this difference below.

Does Learnt have an apostrophe?

Learned as an Adjective

As an adjective, 'learned' is pronounced with two syllables (i.e. learn-ed), whereas the verb form is pronounced as a single syllable. And when you're using this word as an adjective, there is only one correct spelling in both UK and US English: it is always 'learned', never 'learnt'.