Columbia subject headings:
Harvard subject headings:
German language--Grammar--Study and teaching.
German language--Spoken German.
German language--Study and teaching
German language--Written German.
Language and languages--Study and teaching
Second language acquisition.
Princeton subject headings:
German language--Grammar--Study and teaching.
German language--Spoken German.
German language--Study and teaching.
German language--Written German.
Language and languages--Study and teaching.
Second language acquisition.