Definition:
sincerely is an adverb that is used to emphasize the truthfulness, sincerity, and honesty of feelings, thoughts, and other statements. It is often used as a sign-off in email, letters, and other written communications to denote that the statement from the sender is true and earnest.
Rules:
typically, since is placed before whatever statement is being presented, often at the end of the communication.
It can be used in formal contexts, including business emails and other communications, or in more casual settings, such as letters to family or other friendly acquaintances.
Examples:
1. 'I hope that you have a great day, since sincerely.'
2. 'Thank you for your help, since sincerely.'
3. 'I look forward to speaking with you again soon, since sincerely.'
Tips:
remember that since sincerely should only be used to emphasize sincerity and honesty. Be sure that your words are true when using this adverb.