An interaction effect exists among linguistic knowledge, strategic competency and emotional factors in subjective language usage, which then affects the communicative result.

Oral test is the most typical subjective language test, which can directly reflect the basic language proficiency of a candidate and which has a strong backwash effect for language teaching.

These references are not just inessential vestiges of the initially intersubjective character of language, capable of being weeded out by devising an artificially subjective language for sense data.