More formal:
* Informed: "She was informed of the meeting's cancellation."
* Notified: "The students were notified of the upcoming exam."
* Communicated: "The manager communicated his expectations to the team."
* Revealed: "The witness revealed important details about the crime."
More informal:
* Said: "He said he would be back later."
* Explained: "She explained the instructions to the new employees."
* Shared: "He shared his concerns with the group."
* Let know: "I let him know I'd be running late."
* Whispered: "She whispered the secret to her friend."
* Yelled: "He yelled at me for being late."
More specific:
* Confessed: "He confessed to stealing the money."
* Advised: "The doctor advised me to get more rest."
* Promised: "She promised to call me later."
* Warned: "He warned us about the dangers of the storm."
Example:
Original sentence: "The teacher told the students to be quiet."
* Informal: "The teacher said to the students to be quiet."
* Formal: "The teacher informed the students to be quiet."
* More specific: "The teacher instructed the students to be quiet."
Always consider the context of the sentence and the desired tone to choose the best replacement for "told."