Tonic prolongation at the beginning of the phrase.
Music By Women: Phrase Model. Explore the Database (Click on the Chords & Harmonies Filter on the left and select chord category you need.)
Paula Maust, Expanding the Music Theory Canon: Predominant
Diverse Music Theory Examples: Tonic/Subdominant/Dominant, First Inversion Chords (I, IV, ii, V), Supertonic and the Submediant