How would Greece "temporarily" leave the Eurozone?
There´s several possibilities, but they are all speculative. 

My guess is that its not too hard to tell a story like this one: They could leave the monetary union, declare all local deposits and debts to be in drachmas and then move on, printing drachmas and taking them in for tax payments. Later on, when the economy is growing and the fiscal deficit has become manageable, they would apply to be part of the Eurozone again.