My limited resources tell me by rules but do not specify how each ensample use is to be pronounced. It is left up to you to apply the rules and here they are:
1. T-h-e is usually pronounced tha before a consonant.
2. T-h-e is usually pronounced thee before a vowel.
3. Sometimes before vowels, t-h-e is also pronounced tha.
4. For emphasis before titles and names or to suggest uniqueness, t-h-e is often pronounced thee.
5. When used as a preposition meaning per as in "a dollar the dozen," it is pronounced tha.
6. When used as an adverb as in "none the wiser for attending, the sooner the better, the bigger the better, and the better to see you with," it is most often pronounced as tha. "Ambiguous Bill"
