My father and i, along with my grandfather’s .

which element is necessary to complete the sentence?

predicate
phrase
subject
modifier

Predicate

Explanation:

A predicate is a part of a sentence that tells us about the action of the subject. A predicate includes a verb or a modifier governed by the verb in it.

For Example,

The element necessary to complete the sentence is a predicate. In order to complete the sentence, a predicate, that is, action needs to be added.

What is done by the father and 'I' with the help of the 'grandfather' is missing.

So, the correct answer is first option.

answer; i believe the correct answer is (fluctuated);

separation of church and state? not sure what you mean.