when to use tener que or deber in Spanish
seen it's not too different from the English use. Here
just a short summary to keep in mind.
que is used when there is no
degree of freedom of choice, if there
is no alternative for the person to
act then tener
que is the right choice. Even
if the request comes from another
person (and is not caused by nature
or law) tener que is used when this
person has the necessary authority
to demand something without giving
the chance to do something alternative.
que is also used when the logic
says that there is no other choice. Tienes que
trabajar más, si quieres comprar
el coche. = You have
to work more if you want to buy the
car. El juez
dijo que tiene que irse a la cárcel.
= The judge says he has to go to jail.
If it is about an attitude
can be used in Spanish. Tienes que
conocerlo, te va a fascinar. Debes conocerlo,
te va a fascinar. = You have
to meet her, she will fascinate you!!
= You should meet her, she will fascinate
deber is used when
there is an alternative and the acting
person has room for manoeuvre. Debe ir a España,
pero creo que se va a Italia. = He should
go to Spain but I think he goes to
is used with moral principles Debes venerar
a tus padres, pero si te pegan, debes
defenderte. = You should
honour your parents but when they hit
you, you should defend yourself.
conjuntivo is used
of both verbs when assuming something. Tendría
que saberlo. = She should
In negative clauses
deber can't be substituted with tener
que (neither in English!).
The difference between the English use of shall/should
and to have to in opposite to deber
and tener que is
minimal. Deber is used in indicativo and in conjuntivo
20.7), shall is mostly used in the conjunctive form
should. Tener que is
used in indicativo and conjuntivo (again see chapter
have to or also to must
is only used in indicativo. Tener
que is the unavoidable, deber
expresses requirements, demands, attitudes, assumptions