"Stair-ify" a string
Pyth, 63 bytes
V_Q aY?}rN0&quot;aeiou&quot;=hZ?}N&quot;     &quot;=tZZ;Jh.mbYKh.MZYjC.b++*d+JNY*dK_YQ
                         ^^^^^
                         |||||
                         |tabs
                        space

The spaces in the middle is actually a single tab character, but StackExchange renders it as four spaces.
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