Interested in Language
1. I built my house for an hour.
I heard it as an example of how some verbs can change class e.g. from activities to accomplishments:
I walked. (activity) --> I walked to the station. (accomplishment) - I have no problem with this one.
I built my house. (accomplishment) --> I built my house for an hour.(activity) (?)
Shouldn't it be either:
a/ I built my house in an hour. (and then there's no change of class, it's also an accomplishment) or
b/ I was building my house for an hour.