When can you pay me____the money I lent you?

When can you pay me back the money I lent you?

Когда вы можете вернуть мне деньги, которые я вам дал?

What can you pay back?

Can you or can he pay me back the money I lent you?

Can you pay me or him back the money I lent you?

 Can you pay me back the money or the sum I lent you?

You can pay me back the money I lent you, cannot you?