Here are some synonyms for "perfunctorily":
* Mechanically
* Routinely
* Superficially
* Halfheartedly
* Carelessly
* Formally
* Indifferently
Example:
* "She greeted her colleagues perfunctorily, barely making eye contact."
* "The manager reviewed the report perfunctorily, paying little attention to the details."
In contrast to "perfunctorily", words like "enthusiastically", "carefully", and "passionately" suggest a high level of effort and interest.