Columbia subject headings:
Harvard subject headings:
Catalan language--Grammar, Comparative.
Catalan language--Study and teaching
Contrastive linguistics.
German language--Grammar, Comparative.
German language--Study and teaching
Portuguese language--Grammar, Comparative.
Portuguese language--Study and teaching
Spanish language--Grammar, Comparative.
Spanish language--Study and teaching
Princeton subject headings:
Catalan language--Study and teaching--Foreign speakers.
German language--Grammar, Comparative--Romance languages.
German language--Study and teaching--Foreign speakers.
Portuguese language--Study and teaching--Foreign speakers.
Romance languages--Grammar, Comparative--German.
Romance languages--Study and teaching--Iberian Peninsula--Foreign speakers.
Spanish language--Study and teaching--Foreign speakers.