É

Auxiliary

 positiva  cando

Subordinating conjunction

  os

Determiner

  síntomas

Noun

 descritos  previamente

Adverb

  aparecen

Verb

  no

 primeiros  trinta

30

Numeral

 segundos  do

 test.

It is positive when the previously described symptoms appear within the first thirty seconds of the test.

It is positive when the previously described symptoms appear within the first thirty seconds of the test.