When can we use "is" at the end of sentence?

Question

You must leave the furniture as it is. you mustn't move anything.

When can we use the verb to be at the end of sentence?

UPDATE:

The verb be is used in the following patterns:

1. with a noun:

My mother is a teacher. Bill Clinton was the president of the US.

2. with an adjective:

This soup is very tasty. The children were good.

2.1 with the -ing form to make the continuous aspect

We were walking down the street. Everything was wet. It had been raining for hours.

2.2 with the -ed form to make the passive voice

The house was built in 1890. The street is called Montagu Street. This car was made in Japan.

3. with a prepositional phrase:

John and his wife are from Manchester. The flowers are on the table.

British Council

In the above description, the to be verbs is followed by adjective or verb.

So, When can we use the verb to be without adjective or verb?

Answer 1

When it is appropriate.

It is.

This is a correct sentence.

Is he home? Yes, he is.

These are correct sentences.

You can be here whenever I am.

This is a correct sentence. I am (here). The (here) is implied, and can be written, but it is not required.