EXCLAM (书面语中用于表示在交谈时作出回应或引起他人注意或表示惊讶、失望)啊Ah is used in writing to represent a noise that people make in conversation, for example to acknowledge or draw attention to something, or to express surprise or disappointment. (书面语中用于表示在交谈时作出回应或引起他人注意或表示惊讶、失望)啊 [feelings]
I'm meeting Anna Langenbach. Ah, this seems to be the train now.