REMOVE

1. streets
2. buildings (structures)
3. freight cars
4. colleges (buildings)

WHAT

1. Greenwich, Connecticut (1)
2. Visual Works (hierarchy n … (1)
3. black-and-white film (1)
4. bushes (1)
5. dogs (animals) (1)

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WHERE

1. Greenwich, Connecticut (1)

WHO

1. Clyfford Still; Still, Cl … (1)
2. Still, Clyfford (1)

WHEN

1. 1956 (1)
2. 1956 April 11 (1)