Answer:
The correct answer is A) The Coliseum in Rome is the structure that used to host gladiatorial combats.
Explanation:
A simple sentence is identifiable when there are three major components:
Subject + Verb + Object.
The Verb + the Object are both known as Predicate.
A ten-word sentence can still be a simple sentence because of the presence of modifiers, compound subjects, and compound verbs/predicates.
An example of a very basic simple sentence is:
Rome <u>hosted</u><em> combats.</em>
<em />
Rome is the subject.
<u>Hosted</u> is the verb
<em>Gladiatorial combats </em>is the object.
The subject becomes a compound one when you add The Coliseum. That is "The Coliseum in Rome is the structure" becomes the subject.
The verb/predicate becomes compounded when you qualify it using:
"that used to"
This makes the "that used to host" a compound verb. Note that the word hosted has changed to host.
The object - Combat has also changed slightly by the presence of a qualifier - and adjective - gladiatorial.
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