I can’t find any explanation on how can I repay my DAI debt properly. I think I should click first on the "Approve DAI" button on MyEtherWallet's interface or if I use [Oasis.app](https://oasis.app/), then on the "Unlock DAI to continue" switch to make a transaction with these functions. (I assume both do the same thing.)
But I don’t know what I’m actually doing with these functions because I haven’t found any explanation about them, and until I have no idea about something especially in the Crypto world, where transactions are irreversible and the stakes could be high, I don’t even want to poke it with a stick.
**So what happens if I approve or unlock DAI?**
Once I'm done with that, I can repay my DAI debt with the "Submit" button on MEW or with the "Pay back" button on [Oasis.app](https://oasis.app/) after I entered the amount of DAI I want to repay.
**If I payed back my full debt and withdrawn my full collateral, will my Vault be closed in the same transaction where I withdrawn my full collateral or can I borrow more DAI in the future from that Vault without opening another?**
Thank you for your answers!