Use "cross my heart" in a sentence

1. Cross my heart and hope to die, it's all perfectly true.

2. A formula of Asseveration in Maryland and Pennsylvania is, “I cross my heart,” accompanied by the sign of the cross.

3. Stumpfarms And Broadaxes Jack Mould, Python For Data Science For Dummies (For Dummies (Computers)) Luca Massaron, River, Cross My Heart (Oprah's Book Club) Breena Clarke, Development On, Or Affecting, The Flood Plain: Report And Proceedings Of The Committee V