A very common word in English is “the”. But you might notice we pronounce it two different ways!
If “the” is next to a consonant, it will be pronounced [thuh]:
the book [thuh book]
the car [thuh kar]
the man [thuh man]
If “the”is next to a vowel, it will be pronounced [thee] and often has a linking sound [y] to help you easy say the phrase:
the orange [thee (y) oranj]
the ending [thee (y) ending]
the acorn [thee (y) akorn]
So practice the pattern for an improved American English pronunciation.