necessary
The German word 'notwendig' is the equivalent of the English word 'necessary'. It is used to express that something is required or essential. For example, 'Water is notwendig for life' means 'Water is necessary for life'.
It is not necessary to do that.
This sentence is used when expressing that there isn't an obligation, need, or requirement to perform a given action. The verb 'tun' is a general-purpose verb that can be replaced with any other verb to express the unnecessary nature of different actions.
That is not necessarily necessary.
This sentence implies that something might be useful or desirable but isn't strictly necessary. It is often used to downplay the importance or urgency of an action or thing.
He found it necessary to leave.
This sentence demonstrates the use of 'notwendig' in expressing personal judgments or assessments. It shows that the subject ('er/he') considered the action of leaving to be necessary.