Conjugatin hablar
In conjugating "hablar," one is left with the stem "habl." Since it is an "ar" verb, how come first-person singular is "hablo," instead habla? The other conjugations include the "A," so why is the yo form exempted? Thanks.
4 Answers
Hello knowledge,
Welcome to the SpanishDict forum 
I am trying to understand why this should be a problem for you. After all, in English, with the verb to speak, we have:
I speak
You speak
He/ She speakS
I cannot see why a small variation in the conjugaton of a verb in one language should be considered strange but considered acceptable in a different language!
Take the French verb, for example: vouloir = to wish, to want
Je veux
tu veux
Il veut /elle veut
The endings are different and people just accept it but because the French use the personal pronouns in conversation. there can be no confusion.
What I am trying to illustrate is that it is common practice when conjugating verbs in many languages for there to be some variation in the endings of those verbs so that both the speaker and listener/s can know (understand) to whom they are referring to in a conversation. The current conjugation of Spanish verbs is just the way things are. I do not know whether we (still) have any grammarian on Spanish Dict with the expert, in depth knowledge of etymology: that is, the origins and development of language. Our native Spanish speaker, Lazarus might have known why this is so but I believe that this is a very specialised field of knowledge that most people do not possess.
In French, unlike Spanish, the personal pronouns,
eg: je, tu, il, elle, nous, vous, ils and elles have to be used. In Spanish, however, they are normally omitted and native speakers listening know whom the speaker is talking about from the context and the verb endings! 
Sometimes these personal pronouns are used for emphasis or for clarification (to avoid ambiguity)
ex: Yo que tú = If I were you.
I hope this helps
Corrijan mi español si es necesario, por favor
Here is a basic lesson on regular verbs
http://www.studyspanish.com/lessons/regverb1.htm
The regular endings are what they are, they are attached to the stem that you correctly found:
o, as, a, amos, áis, an
The language simply developed in a way that left an a as part of the endings for everything but the first person. Perhaps a scholar of the development of the language could tell you what the original endings were in Latin, and when they evolved to these forms, but for the most part it is best to just accept them as they are.
Yo hablo
Tú hablas
Él habla
The model is the verb amar
Yo amo
Tu amas
Él ama
Spanish is a direct descendant of Latin. If you examine the conjugation of the verb "to love" in both languages, this connection becomes very clear:
Latin: amó, amás, amat, amámos, amátis, amant
Spanish: amo, amas. ama, amamos, amáis, aman
It is interesting to note that if you were to remove the "t" from the Latin conjugation, you would have the Spanish version (ignoring the stress)
As to why Latin uses or used "o" as the ending for the 1st person present indicative, is beyond me
Cheers
