keys
The word 'Schlüssel' is the German translation for 'keys'. In German, 'Schlüssel' is a masculine noun and is used in the same context as in English, referring to a small piece of shaped metal with incisions cut to fit the wards of a particular lock, which is used to lock or unlock it. It can also be used metaphorically, such as in the phrase 'the key to success', meaning a crucial element or factor that is necessary to achieve success.
Where is my key?
This phrase is often used when a person is looking for their key, usually when they are about to leave the house or lock something up.
The key does not fit into the lock.
This sentence could be used when a key doesn't fit a lock. It can refer to both a physical key and lock or metaphorically to solving a problem or puzzle.
The key to a happy life is love.
This is a more metaphorical use of the term 'Schlüssel', meaning 'key'. In this context, 'key' refers to an essential element or solution.