I was seen to enter the building.
I was seen entering the building.
The sun was seen rising in the horizon.
The boys were seen cleaning the room.
She was seen writing a complaint against the restaurants.
One more thing:
In English, the expression be seen to be doing something means to make sure that other people notice you working hard or doing something good
Example: The government must be seen to be doing something about the rise in violent crime.
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