Original sentences: sir edmund was anxious to explore antarctica. so was his son, cecil. combined sentence: sir edmund and his son, cecil, were anxious to explore antarctica. does the combined sentence use a compound subject, compound verb, or compound object?

The combined sentence uses a compound subject.

Explanation

The subject of a sentence is said to be the protagonist.  

It maybe a person, place, or idea.  compound subject using sentences has multiple subjects (two or more) joined by 'and' or 'or'.

When using multiple subjects, the use of subject-verb agreement is important to express the proper idea of the sentence.

Here,  Sir Edmund and Cecil are subjects.

As there are two subjects, this is a sentence that uses two subjects, hence it is a compound subject.

the book's theme is the moral ambiguity of the iranian revolution, history of middle eastern relations and the process of growing up during war. it sheds light on the stereotypical views of middle eastern culture and religion.

the author explicitly portrays the issues of class disparities and racism continously throught the whole novel.

the relationship between parents and childrens, the abandonment of faith, modernity vs fundamentalism and class conflict are the 4 main panels that this novel englobes.

hope this , if you would like me to be more specific about a specific excerpt let me know : )

i need some details.