Marriott concluded that, of the four major variables examined, the
learners became very competent in handling polite formulaic expressions
after their year abroad. This was seen in their native-like management of
appropriate formulae in the opening and closing sequences of the interview,
and also in the opening and closing segments of the role play in
which they took part. They were not able to do this before the stay abroad.
They had most trouble with the selection of style, tending to use a mixture
of plain and polite styles which was not the Japanese norm. Marriott
proposes primarily an input explanation for the lack of complete mastery
of sociolinguistic competence in this area: the non-reciprocal nature of
variation. The learners in this case did not get the polite form in the
speech of older native speakers to them. As well as the input problem,
Marriott suggests interference from the first language, English, which
lacks such explicit stylistic variation rules, and also the complexity of the
Japanese system.