1. makes a solemn promise or oath
2. uses profane or offensive language
3. states or affirms earnestly and emphatically

Examples

• She swears to tell the truth in court.
• He swears by his grandmother’s recipe.
• The witness swears on the Bible.
• My brother swears when he’s angry.
• She swears she locked the door.
• He swears he saw a ghost last night.
• The coach swears his team will win.