Usage patterns
〈事〉が厳かに行われるfor a ceremony or event to be conducted solemnly
The wedding ceremony was conducted solemnly.
厳かな雰囲気a solemn atmosphere
A solemn atmosphere hung over the venue.
厳かな儀式a solemn ceremony or ritual
A solemn ritual was held at the shrine.
厳かに宣言するto declare something solemnly
He solemnly declared independence.