Monophthongs are single vowel sounds in a syllable with stable articulation. They differ from diphthongs (two vowel sounds). Examples in English include /iː/, /ɪ/, /uː/, /ʊ/, /e/, /æ/, /ʌ/, /ɑː/, /ɒ/, /ɔː/, /ə/, and /ɛː/. They are crucial for clear word distinction in spoken English