Pronouns may be used in sentences to separate the subject and the object (predicate), in situations where there is no verb.

For example:

هَذا هُوَ التفاح اخضر - This is a green apple.

Compared to a noun phrase:

هَذا التفاح اخضر - This green apple…

Another example:

هَذَهِ هِيَ الصورة - This is a picture.

هَذَهِ الصورة - This picture…

Sometimes the pronoun of separation is omitted if the meaning is nonetheless clear without it.