In the following passage, some of the words have been left out. Read the passage carefully and select the correct answer for the given blank out of the four alternatives.

The phrase consists usually of a few words which denote a single idea that __________ a separate part of a sentence. In this respect it differs from the clause, ___________ is a short sentence that forms a distinct part __________ a composition, paragraph, or discourse.Correct phrasing is _______________ by rests, such rests do not break the ______________ of a thought or the progress of the sense.