Little is known about his activities during this last period.

But if I didn't know about your activities, we wouldn't be having this conversation either.

However, nothing more is known about his activities after this time.

But what do you know about the son's recent activities?

Little is known about Wang's activities for the next decade.

Little is known about Day's activities in his later years.

"What do you know about your father's activities during the war?"

Not much is known about his activities over the next six years.

"And you believe whoever it was who talked also knew about your own activities?"

Or at least that he'd have warned me, given all he seemed to know about my recent activities.