Question

Later, King led a famous march on Washington and worked for equal rights.
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(Is this sentence correct? The use of the preposition 'on'?)

Answer 1

Usually, we'd use the preposition "to" in a sentence like this, but for this particular march, the preposition "on" has always been used. I think this is because he was leading such a large group of people, and because they were not going there for pleasure. They had a definite purpose.