Help needed with some writing questions!!!

<p>1- Although the bicycle was not very fast it [must have been] fun to ride.
Should "must have been" be replaced with "was" ? So that the sentence reads :
Although the bicycle was not very fast it was fun to ride.
2- It was English [in origin].
Is this correct or "in origin" should be replaced with "by origin" ?</p>

<p>bump</p>