動詞 round off:

1. make round
   同義詞：round, round out, round off
2. bring to a highly developed, finished, or refined state
   同義詞：polish, round, round off, polish up, brush up
3. express as a round number
   同義詞：round off, round down, round out, round

1. He rounded off his short speech by thanking everyone who had assisted him.
   他對幫助過他的每個人表示了謝意，以此結束了他簡短的講話。
2. She rounded off the corners of the table with sandpaper.
   她用砂紙把桌角打磨光了。