1. They tacitly agreed to keep their plan a secret.（他们心照不宣地商定保守他们的计划。）
2. By staying silent, she tacitly admitted that she was at fault.（通过保持沉默，她默许地承认了自己的错误。）
3. His refusal to answer the question was tacitly understood as a sign of guilt.（他拒绝回答这个问题，默许地被理解为有罪的迹象。）