* Guarantee: This is the most direct equivalent, meaning to promise or assure something. For example: "The bank guaranteed the loan."
* Stand surety for: This phrase means to be responsible for someone else's debt or obligation. For example: "Her father stood surety for her loan."
* Underwrite: This verb means to agree to be financially responsible for something, typically an insurance policy or loan. For example: "The insurance company underwrote the policy."
The best choice depends on the specific context of what you are trying to express.