Cách sử dụng
"Swear blind" means to strongly and confidently insist that something is true, even if others doubt it or there is no proof of it. You might use this expression in a situation where someone doesn't believe you about something, and you want to emphasize how strongly you believe it to be true. For example, "I swear blind that I saw a UFO last night!" means that you are certain you saw a UFO, even if others don't believe you or there is no concrete evidence to support your claim.