A sentence usually has a subject and predicate, both may also have modifiers.
You should be able to identify the main parts of the basic sentence unit, which are Subject, Verb and Object.
The subject names what the sentence is about, the verb tells what the subject does or is, and the object receives the action of the verb.
A subject and verb combination is the simplest English sentence. Although many other structures can be added to this basic unit, the pattern of SUBJECT plus VERB (or SUBJECT plus VERB plus OBJECT) can be found in even the longest and most complicated structures.