When using deber
to express an attitude the question is how the persons
attitude is towards the issue.
I liked the book so much I had to
read it again right away. Nobody
is actually forcing it on me but I really had to do
it. It was my inner attitude that made me do it.
In Spanish there are two possibilities.
Testing with Google we found a slight preference for
tener que.
The sentence
"tienes que leerlo" is found 144 times
in Google.
Si te atreves a
encarar la verdad a pesar de la incomodidad,
tienes que leerlo.
= If you dare to face the truth how uncomfortable
it might be you have to read it.
Un día estaba en
mi casa y mi hija me mostro el libro y me
dijo "Papá este libro es genial
tienes que leerlo" y yo le contesté
"no, son libros para chicos" pero
con el tiempo todos en su escuela los estaban
leyendo y dije "Bueno, voy a leerlos!
y cuando terminé dije, es genial
tengo que hacer una pelicula sobre esto. = One day
I was home and my daughter showed me a book
and said: "Dad, this book is great
you have to read it" and I answered
"No, these are books for children"
but with the time everyone in her school
had been reading them and I said: "Good,
I will read them!" and when I finished
I said it's great I have to make a film
about this.
The sentence
"debes leerlo" is found 87 times in Google.
¡Debes leerlo
para saber si es lo que buscas!
= You have to read it to know if it is what
you look for.
El contrato es un documento legal, debes
leerlo cuidadosamente y estar seguro de
que entiendes toda la información
antes de firmarlo. = The contract
is a legal document, you have to read it
carefully and be sure that you understand
all the information before you sign it.
Let's have another example:
The sentence
"tienes que probarlo" is found 183 times
in Google.
Yo le dije que en
esta vida tienes que probarlo todo.
= I told him that in this live he has
to try everything.
No se puede explicar lo que se siente cuando
estás volando. Tienes que probarlo. = It's impossible
to explain what you feel when you are flying.
You have to try it.
The sentence
"debes probarlo" is found 139 times in
Google.
Debes probarlo para
saberlo con certeza y poder decirle al mundo
sin esconderte ¡ Si, soy gay!. .
= You have to try it to know with certainty
and that you can tell the world without
hiding. Yes, I'm gay.
Existe un ODBC que funciona en Win95/NT
pero debes probarlo en W2K. = There
is an ODBC interface that works with Win95/NT
but you have to test it on Windows 2000.
So, you see. Actually you can do both when talking about
the inner attitude. But if you want to do it the easy
way just do it as in English: with tener
que.