What drops out in fast speech
In everyday speech you rarely hear para que or cansado. Native speakers say pa' que and cansao. This isn't sloppiness; it's the normal form in relaxed conversation, across all levels of education, much like English gonna. If you don't know these forms, you lose the thread when listening.
Shortened words
You'll hear these short forms in almost every Spanish-speaking country. Before a vowel, pa' merges with the next word: pa'l from para el, pa'lante from para adelante.
Widespread everywhere
Te lo digo pa' que lo sepas.
[[ˈpa ke] instead of [ˈpaɾa ke]]
I'm telling you so you know.
pa' que = para que
Me voy pa'l trabajo.
[[pal tɾaˈβaxo]]
I'm off to work.
pa'l = para el
To' el mundo lo sabe.
[[ˈtoel ˈmundo]]
Everybody knows.
to' el = todo el, the o and e move together
Na' más llegar, me llamó.
[[na ˈmas]]
The moment I arrived, she called me.
na' más = nada más
The disappearing d
The soft [ð] between vowels is weak and often vanishes completely in conversation. It happens most in the ending -ado. In Spain -ao is heard almost everywhere in casual speech, and in many parts of Latin America too. In Mexico the d is usually kept.
Full form and conversational form
Estoy cansado.
[[esˈtoj kanˈsaðo]]
I'm tired.
Talks, the news, slow speech.
Estoy cansao.
[[esˈtoj kanˈsao]]
I'm tired.
Relaxed conversation.
Word-final d is weak as well: usted, verdad and Madrid often sound like usté, verdá and Madrí in conversation.
More cases
Ya he terminao.
[[ja e teɾmiˈnao]]
I'm done already.
Está bien, ¿verdá?
[[beɾˈða]]
It's fine, right?
Regional, for understanding first
Other reductions belong to a particular region. You need to understand them, but it's best to adopt them only once you live there. Otherwise they sound put on.
Typical of certain regions
Pos sí, ¿no?
[[pos ˈsi]]
Well, yeah, right?
pos = pues, mainly Mexico
¿'Tons qué hacemos?
[[ˈtons ˈke aˈsemos]]
So what do we do now?
'tons = entonces, mainly Mexico and Central America
¿'Tá bien?
[[ˈta ˈβjen]]
Is that OK?
'tá = está, especially in the Caribbean
¿Cómo estás?
[[ˈkomo ehˈtah]]
How are you?
The s becomes a breath, in Andalusia, the Canary Islands and large parts of Latin America.
More marked than -ao are -ío for -ido (he comío) and -á for -ada (no pasa ná). In many places they count as rural or very slangy.