I read that the definite article is pronounced differently depending on the word that follows it. Which is the exact pronunciation of the?
I’m adding this answer because no one seems to have used IPA, or explained the matter simply. The word has three standard pronunciations, which vary by context.
The definite article ‘the’ is normally pronounced
/ðə/ before a consonant sound and
/ði/ before a vowel sound. Neither of these is a stressed syllable.
However, it also has a ‘stressed’ pronunciation used for emphasis, which is always
/ðiː/ no matter what sound should follow it. The vowel here is held longer than in the unstressed version.
That’s really all there is to it.
If the following word starts with a vowel it's pronounced like 'thee'.
For other details I would recommend Pronunciation of the voiced & voiceless "TH" sound.
There is no hard-and-fast rule for the pronunciation of this word, as it depends strongly on where you grew up speaking. I am from the northern United States, so in my dialect, I have "the" before words that start with consonants and "thi" before words that start with vowels, usually. I also use "thi" to add emphasis (as in "That is the best pie I have ever had").
That's my two cents. Just keep in mind that it may be different for other regions of the US and other countries.
I'm in Toronto, Canada. The region is useful info if we are going to "argue" about pronunciations. When I hear someone say "thuh army", I hear an uneducated person (or a non-native speaker, if you want to give the person an out). I've read that people in the South always say "thuh", regardless of the word following. I'm hearing "thuh" so often now before vowel sounds, that I'm sure it's more than just in the South.