c. 1400, "happening on some particular occasion," also "sometimes, happening as occasion presents itself, without regularity," from occasional + -ly (2).
权威例句
1. His prose is vigorous and dense, occasionally to the point of obscurity.
他的散文文笔有力、内容庞杂,有时几近晦涩。
2. Occasionally a patient is so debilitated that he must be fed intravenously.
偶尔会有病人过于虚弱,必须通过静脉注射进食。
3. Mrs Southern listened keenly, occasionally breaking in with pertinent questions.
萨瑟恩夫人兴致勃勃地听着,间或插话问一些相关的问题。
4. My father would occasionally go to his Masonic lodge.