The low-pitched tone of a phone alerted Erica to a call for her services.

His tone alerted Tippoo Tip to the importance of the next request.

The man's tone of voice had immediately alerted her.

The tone of his voice alerted Zouga, and he scrambled to his feet.

The somber tone of Lauren's greeting alerted Alan that something was wrong.

"Ready-" The adept did not turn to address any of our group, but his tone alerted us.

The dry tone alerted her, but she was too delighted to mind being teased.

The flat tone of Picard's voice should have alerted Crusher to what was coming, but her mind rejected the implications.

His tone alerted me that, once again, he knew something he was not going to share.

The urgent tone of the first officer's voice alerted Picard at once that there was more trouble afoot.