An easy idiom today about gold — ‘as good as gold’.
We use this idiom if we want to say that something or someone is very good. It may be a machine or an animal for example that is reliable and trustworthy. Perhaps it could be used to describe somebody who is very well behaved or reliable. Here are two examples for you.
‘The old car is still going well and the engine is as good as gold. It is very reliable indeed.’
‘My littler son is really great and now and he's as good as gold when we travel in the car. No problems at all.’
‘as good as gold’ — ‘bagus sekali atau bisa diandalkan’
Source: www.kangguru.org