In the word eight there are just two phonemes - eight?

The statement is incorrect; the Word "eight" actually contains three phonemes: /eɪ/, /t/, and the silent phoneme /h/. The sound /eɪ/ represents the vowel sound in "eight," while /t/ is the final consonant sound. The /h/ is not pronounced but is part of the spelling. Thus, "eight" has more than just two phonemes.