1. to gradually increase or create anticipation, hope, or belief that something good will happen
The marketing campaign built up expectations for the new product launch.
A campanha de marketing criou grandes expectativas para o lançamento do novo produto.
2. to develop or establish high standards or hopes that may be difficult to meet
Don't build up expectations too much or you might be disappointed.
Não crie expectativas muito altas ou você pode se decepcionar.