Assertion: pregnancy test's line | /r/AtLocation | square window
Facets:
value: as a control
type: MANNER
Source sentences:
text: A line will appear in the square window as a control to show that you have done the test correctly.
text: If no line appears in the square window, the test result is invalid.
text: As long as a (+) symbol appears in the round window and a single line appears in the square window, the result is positive.