In many of the Romance languages (and also in German and other Germanic languages, contractions are often obligatory. Certainly, they don't use apostrophes like we do in English (but Romanian uses hyphens). I teach an English as a Second Language class, and a couple from Angola was trying to tell me that Portuguese has no contractions. This is, of course, ridiculous. It's just that they don't think of them as such since they are more or less completely lexicalized In English, contractions are optional in all cases, and the uses are pragmatics determined -- that is, they are used when appropriate and not used when they are not. In other languages, the usage is more or less obligatory:
In Spanish, the words de 'of' and a 'to' must make contractions with the masculine singular definite article el 'the.' So, 'of the man' and 'to the man' come out as del hombre, al hombre, never *de el hombre, a el hombre.
Portuguese is full of contractions, and forms them with many common prepositions and all of the articles: de, a, em, por + o, a, os, as, um, uma, uns, umas 'of/from, to, in/on, for' and 'the, a':
- do cão,
- dos cãos,
- dum cão,
- duns cãos,
- ao cão,
- aos cãos,
- no cão,
- nos cãos,
- num cão,
- nuns cãos,
- pelo cão,
- pelos cãos
'of the dog, of the dogs, of a dog, of some dogs, to the dog, to the dogs, on the dog, on the dogs, on a dog, on some dogs, for the dog, for the dogs.' The same paradigm works for the feminine, mesa 'table': da mesa, das mesas, duma mesa, dumas mesas, à mesa, às mesas, na mesa, nas mesas, numa mesa, numas mesas, pela mesa, pelas mesas. There are also some less obligatory contractions: d'água 'of the water.'There are also many other contractions involving prepositions and other common words, like aqui 'here'.
French also has a series of contractions involving prepositions + articles: de + le = du, de + les = des, à + le = au, à + les = aux. but it doesn't stop there in French. French forms obligatory contractions like that's its job. Singular articles, both masculine and feminine, form contractions with nouns beginning with vowels: le + orange, la + eau = l'orange, l'eau, 'the orange, the water.' Also, clitics and similar Cons.+ schwa words contract similarly: ce + est = c'est, ne + est = n'est. similarly, 'if he, if they': si + il(s) = s'il(s). In French, contractions occur all over, and they are certainly obligatory, and one of the hallmarks of the language.
In Romanian, there are some colloquial contractions, such as 'I don't have, You don't have': nu + am = nam, nu + aveţi = naveţi. But when dealing with tenses, Romanian makes use of many particles, which combine all over the place (Romanian often prefers periphrastic forms instead of Latin-like complex synthetic forms. For instance, it expresses the subjunctive with să + verb, rather than a whole new form like in Spanish). For instance, in Romanian, the past is formed like in French, with 'have' + 'participle': am mers, aţi mers I/you went. But contractions appear when a reflexive is used: a se duce - to go (also) -
... dus: I/you/he.she.it/we/you/they went. These contractions are obligatory.
- mă + am = m-am
- te + ai = te-ai
- se + a = s-a
- ne + am = ne-am
- vă + aţi = v-aţi
- se + au = s-au
There are also contractions with the subjunctive particle să: 'I want to see her' Vreau s-o văd = Vreau să + o văd. 'I want to see him' Vreau să-l văd = Vreau să + îl văd. Finally, 'from in' - de+în = din, 'in the (masc. & fem.):' în + un, în + o = într-un, într-o are similar to contractions in other Romance languages.
German, while not Romance, does do similar things: an dem tisch = am tisch 'on the table,' for instance. But there are also non-obligatory contractions, such as the conversational Wie geht's = Wie geht + es 'How's it going = How goes it?'