have sth. at one's fingertip
1. 精通某事物
David seems to get the whole business at his fingertip.
戴维似乎对整个事件了如指掌。
to one's/the fingertips
1. 完全地
He is a British to his fingertips.
他是个地道的英国人。
习惯用语have sth. at one's fingertips1.■手头有某物随时可供应用2.■精通某事to one's fingertips1.■完全地, 彻底地(He was an Englishman to his fingertips. 他是一名纯血统的英国人。)to the fingertips1.■完全地, 彻底地(He was an Englishman to his fingertips. 他是一名纯血统的英国人。)