This is the 16812th most frequent Polish word.
wykazały
"Showed" or "demonstrated" (past tense, plural).
In this sentence, 'wykazały' describes the result or conclusion derived from scientific research.
Badania wykazały, że ćwiczenia fizyczne poprawiają zdrowie.
Research has shown that physical exercise improves health.
Here, 'wykazały' conveys that the person's reactions were indicative or revealing of their lack of understanding.
Jego reakcje wykazały brak zrozumienia sytuacji.
His reactions demonstrated a lack of understanding of the situation.
In this context, 'wykazały' is used to present the results of an analysis or study.