The police are now monitoring criminal/gang/drug 'activity' in the area.
There has been an increase in the city's (level of) economic 'activity'.
The instruments are used to detect volcanic 'activity' on the island.
(..) Whoa, are we inside my brain right now? - It's big. I must be smart. Mm-hm. I'm not hearing a lot of activity here. I don't think he's ever had an original thought. In his life. For instance, one time I wanted to have... ...a bunch of my friends (..)2014 The Lego Movie