alertness

名词 alertness:

1. the process of paying close and continuous attention
   同义词：watchfulness, wakefulness, vigilance
2. a state of readiness to respond
   同义词：alerting
3. lively attentiveness
   同义词：sharp-sightedness, on the qui vive

1. Emily is a Londoner born and bred and, for a woman some years past the allotted span, of a truly remarkable vigour and alertness.
   埃米莉生在伦敦长在伦敦，虽已年逾古稀，但实在令人惊讶的是，她仍精力充沛，耳聪目明。