bekanntlich
Translation
as is well known, famously, notoriously
Examples
Er ist bekanntlich sehr beschäftigt.
As is well known, he is very busy.
Bekanntlich ist Berlin die Hauptstadt Deutschlands.
As is well known, Berlin is the capital of Germany.
Grammar Patterns
As an introductory adverb: as is well known... Bekanntlich ist heute ein Feiertag.
Similar Words
offensichtlich (obviously), anscheinend (apparently)
Etymology
Composed of 'bekannt' (known) and the adverb-forming suffix '-lich' (like '-ly'). It literally means 'known-ly'.
Memory Tips
Recognize the root word 'bekannt' (known). The '-lich' suffix turns it into an adverb meaning 'as is known'.