Columbia subject headings:
English language--Study and teaching--Foreign speakers.
Interlanguage (Language learning)
Language and languages--Study and teaching.
Language and languages--Variation.
Second language acquisition.
Harvard subject headings:
English language--Study and teaching--Foreign speakers
Interlanguage (Language learning)
Language and languages--Study and teaching
Language and languages--Variation
Second language acquisition.
Princeton subject headings:
English language--Study and teaching--Foreign speakers.
Interlanguage (Language learning)
Language and languages--Study and teaching.
Language and languages--Variation.
Second language acquisition.