I worked feverishly to get the test completed.
The people feverishly sent calls for help.
I feverishly layed in bed.
The crew is working feverishly to finish our project on time. She's only spoken feverishly, today.
yes feverishly is an adverb. It tells how ex: He wrote feverishly to complete is work on time. feverishly describes how he wrote.
Climactic is an adjective that pertains to a climax of a story. The word is kind of over the top, so be careful of how often you use it. "Jane worked feverishly so that she could have a great climactic ending to her novel."
calmly
Two main uses I can think of: "Sick and frail, the old man moaned feverishly as he covered himself with a blanket." "The crazy spinster feverishly warned of impending Armageddon to passers by."
Depending on the usage, the opposite of the adverb feverishly could be calmly, or deliberately, or slothfully. Others could be coolly, serenely, or unexcitedly.
synonym
A SENTENCE WITH THE WORD OUNCE A SENTENCE WITH THE WORD OUNCE A SENTENCE WITH THE WORD OUNCE A SENTENCE WITH THE WORD OUNCE
a sentence with the word variety
The word is sentence