The word(s) "supposed" appears 3 time(s) in 3 verse(s) in Quran in Muhammad Pickthal translation.

(1) And when We shook the Mount above them as it were a covering, and they supposed that it was going to fall upon them (and We said): Hold fast that which We have given you, and remember that which is therein, that ye may ward off (evil).

(سورة الأعراف, Al-A'raaf, Chapter #7, Verse #171)
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(2) And lo! we had supposed that humankind and jinn would not speak a lie concerning Allah -

(سورة الجن, Al-Jinn, Chapter #72, Verse #5)
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(3) And indeed they supposed, even as ye suppose, that Allah would not raise anyone (from the dead) -

(سورة الجن, Al-Jinn, Chapter #72, Verse #7)
(Arabic, Transliteration, Urdu (Ahmed Ali), Urdu (Jalandhry), Farsi, Yusuf Ali, Shakir, Picthal, Mohsin Khan, French, Spanish, Indonesian, Malay, German, Bosnian, Russian, Dutch, Italian, Portuguese, Tafsir - Jalal ad-Din, Tafsir - King Fahad Quran Complex)