(US) Can /kən/ – Can’t /kænt/
(UK) Can /kæn/ – Can’t /kɑnt/
How can we tell the difference between “can” and “can’t”? Though it’s subtle, there is still a difference in the pronunciation of these two words.
I can go.
I can’t go.
You can instantly tell the difference between “can” and “can’t” when the British pronounce them because there’s a clear difference in the vowel sound between the two words “can” /kæn/ and “can’t” /kɑnt/.
However, it is a bit difficult for non-native speakers to tell the difference between “can” and “can’t” when the Americans pronounce those words, especially when they speak fast.
The trick is to pay more attention to the length of the vowel in “can” and “can’t”. In “can’t” the vowel sound ‘a’ is pronounced longer /æ/ while in “can” the vowel sound ‘a’ is de-stressed; it is pronounced a bit quicker and reduced to a schwa /ə/, sometimes it sounds sort of like /ɪ/.
I /kən/ go.
I /kɪn/ go.
Check out this video from Elemental English: