Два раздела науки о языке - синтаксис и punctuation - always studied together. Simple cases of placement of commas, for example, a mandatory comma before the authoring unions A and BUT, usually do not cause difficulties. But in order to isolate minor clause members, knowledge of the basic syntax is necessary.
Under certain conditions, secondary members may be separated from two sides by commas, including the circumstance.
The circumstance in the sentence answers the questionsadverbs, as it indicates a sign of action or, much less often, a sign of a sign. Nevertheless, not only an adverb, but also any independent part of speech can act as a circumstance.
Another thing - clarifying the circumstance. Examples of this kind are harder to find: they are not so obvious.
What is the clarifying circumstance?
The clarifying members, as is already clear from the term itself, clarify the information contained in the sentence:
All childhood friends, (who exactly?), Especially Mikhail, are very dear to me.
Dark, (which specifically?) Almost coal-black, eyes stood out on his pale face.
A little girl ran into the room (which one?) Not older than our son.
Refinement is always separated either by commas or dashes.
Separate clarifying circumstance in most cases specifies the time and place of action.
We left late in the evening, (when exactly?) At eleven o'clock.
At the end of August (when exactly?) On the twenty-fifth, my only brother was born.
The clarifying circumstance of the place details, narrows the information about where the event described in the sentence occurs:
Andrei lives quite close to us, (where exactly?) In a five-minute walk.
Ahead (where exactly?) In the very center of the road, we noticed a huge trench.
Last summer we returned from another city, (from where exactly?) From Vladivostok.
My girlfriend moved to the October district of the city of Samara, (where exactly?) On Michurin Street.
Less common is clarifying the circumstance of the action:
The soldiers tried to talk as quietly as possible, (how exactly?) Almost in a whisper.
Perepyolkin listened to me attentively, (how exactly?) With some special respect.
Separated circumstances and with other values.
Understanding the context of a sentence is important for correct placement of punctuation marks:
Artists performed on the square in the city center. (The square is located in the central part of the city)
Artists performed on the square in the city center. (Artists perform on the square located in the center of the city).
Tip in isolating clarifying memberssentences is intonation. But you shouldn’t focus only on semantic pauses in the speech flow, it is better to pay attention to the syntactic role of the structure and choose a question for it.