n.熟练；精通
He made little proficiency in literary accomplishments. 他在文学方面成就不多。
How do you think of your proficiency in written and spoken English? 你认为你的书面英语和口语熟练程度如何?
You need some proficiency in book - keeping for this job. 干这项工作你需要在记帐方面熟练。
