Among the most basic concepts that high school students once graduated knowing were the four kinds of English sentence: simple, compound, complex, and compound-complex.
Because of its name, a simple sentence would seem to be the easiest to identify. Apparently not.
A reader asked me about a sentence her child had been asked to identify as to kind:
Harry bent down and picked them up one by one, dropping them back in the boxes.The reader thought the sentence might be complex because “‘dropping them back in the boxes’ is a dependent clause.”
The sentence, however, is simple. To make this clear, a review of terms is called for.
Clause: A clause is a group of words having a subject and a predicate.
Predicate: The predicate is what is said about the subject. The predicate will contain a main verb.
Main verb: A main verb shows tense. Such a verb is called a finite verb.
Independent clause: An independent clause is made up of a subject and predicate that make sense standing alone as a sentence. Another name for an independent clause is main clause.
That takes care of the terms; now for the analysis.
Dropping is not a main verb. Dropping is the participle form of the verb to drop.
A participle can be part of a main verb only if it is used with a helping verb indicating tense:
The children were dropping rocks down a hole in the garden. (past continuous tense)
The children are dropping rocks down a hole in the garden. (present continuous tense)
In the sentence under discussion, dropping has no helping verb so it cannot be the main verb in a clause. It is nonfinite. That means it does not indicate past, present, or future time. In the sample sentence, dropping introduces a participial phrase: dropping them back in the boxes. The participial phrase is used adjectively to describe Harry.
Another feature of the simple sentence that sometimes causes confusion is the fact that a sentence may have a compound subject and/or a compound verb and still be a simple sentence:
Mary and Jack live in Rhode Island. (compound subject, single verb)
My father and all my uncles hunt in the fall and fish in summer. (compound subject, compound verb)
In our sample sentence, Harry is the subject; bent down and picked up is a compound verb that says something about Harry.
Harry dropping them back in the boxes is the complete subject and bent down and picked them up one by one is the complete predicate.