Which word or phrase is a synonym for the word doctrine?

Read the sentence. our band practices on mondays at josef’s thursdays at lena’s and saturdays at my house. what is the correct punctuation

Why is it important to include a descriptive subject heading? it in sorting the topics. it the recipient see its importance. e-mail programs won’t allow e-mail to be sent without it. it keeps junk e-mail separate from important e-mail.

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