The word intensively 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 intensively
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Seven Letter Word Alert: (23 words)
enliven, enstyle, evilest, eyeslit, inlines, instyle, intense, invents, invitee, invites, lenient, lenites, linnets, seventy, syenite, sylvine, sylvite, tensely, tensile, tinnily, veinlet, vinelet, yeelins