Ameliorate the End of Reconstruction

Directions: ameliorate, or improve, the following sentence. There are three missing commas.
In 1877 President Rutherford B. Hayes withdrew the last federal troops from the South and the bayonet-backed Republican governments collapsed thereby ending Reconstruction.

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Suggested Answer:
In 1877, President Rutherford B. Hayes withdrew the last federal troops from the South, and the bayonet-backed Republican governments collapsed, thereby ending Reconstruction.