The word(s) "diligently" appears 3 time(s) in 3 verse(s) in Quran in Abdullah Yusuf Ali translation.

(1) Thus do we explain the signs by various (symbols): that they may say, "Thou hast taught (us) diligently," and that We may make the matter clear to those who know.

(سورة الأنعام, Al-An'aam, Chapter #6, Verse #105)
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(2) (Joseph) said: "For seven years shall ye diligently sow as is your wont: and the harvests that ye reap, ye shall leave them in the ear,- except a little, of which ye shall eat.

(سورة يوسف, Yusuf, Chapter #12, Verse #47)
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(3) And He hath made subject to you the sun and the moon, both diligently pursuing their courses; and the night and the day hath he (also) made subject to you.

(سورة ابراهيم, Ibrahim, Chapter #14, Verse #33)
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