It is differnt in spanish than in french or other languages, since each word is an independent one, so you must end the pronunciation of the first word before you start the next one. When singing however, there is a common thing that when you find a "diptongo (http://es.wikipedia.org/wiki/Diptongo)" or Diphthong in the connection of two words, then it will be pronounced like if it was part of one word... A bientôt mon ami, bonne chance!

You have to pronounce them separately...

oh thats common in languages so when a spanish speaker is talking sometimes could sound like : "mirallí" but the correct voice is "mira allí" (but it depends of each spanish accent) this is coz som spanish people speak quicky but if u say mira alli s percect, the people understand it and is correct. is it like a english when someone say: "i din't drink enough" and sounds like:"I didn't drin knough"