The word instructive is playable in Words With Friends™, no blanks required. Because it is longer than 7 letters, you would have to play off an existing word or do it in several moves.
Words With Friends™ Letter Score: 20
Highest Scoring Words With Friends™ Play In The Letters instructive
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Seven Letter Word Alert: (43 words)
cistern, citrine, cittern, cretins, cuisine, cursive, cutters, encrust, entrust, inciter, incites, incrust, incurve, intrust, intuits, invects, inverts, inviter, invites, irenics, nitrite, nittier, nutsier, nutters, nuttier, retints, revisit, revuist, sericin, stivier, striven, stunter, tiniest, tinters, tintier, trisect, trivets, uniters, unities, unrivet, uveitis, virtues, vitrine