be identical
The German word 'identisch' is used in the same way as the English word 'identical'. It is used to describe things that are exactly the same or match each other completely. For example, 'Die Zwillinge sind identisch.' means 'The twins are identical.' or 'Die beiden Antworten sind identisch.' means 'The two answers are identical.'
The two objects are identical.
This sentence is used to describe when two objects are exactly the same in all noticeable aspects. 'Identisch' means 'identical' in English, and is used in the context of comparing two or more things.
Our ideas are not identical.
This sentence is used when two or more people have different ideas about something. The word 'nicht' makes the phrase negative, so 'nicht identisch' means 'not identical'.
Her actions are identical to his.
This sentence is used to compare the actions of two different people, and declares them to be the same. The preposition 'mit' is used to express 'to' in this context.