d97e4113__Building_Things___Muppet_Wiki__Segment
[Description] Dorothy wants to know how you build a tower with blocks. Telly also makes his first of several recurring appearances in the episode, carrying a long wooden plank across the frame of the camera... in triplicate, each version of himself carrying a portion of the plank. [Segment] 
Dorothy's Question
Elmo's World: Building Things - Muppet Wiki
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