Hello Cooklava,
My apologies for missing to see your second post,I don't know how that happened :roll: First to tell you that I'm very very glad it's helped you. I believe it is a good direction for learning on the matter. I really refrain from giving explanation here on forum since my english is not that good and it would be wrong to mislead somebody with giving false explanation,so I've tried to be as accurate as possible in explaining,and proofread everything I've written. Of course,you should use some good grammar to expand your knowledge and draw your own conclusion from all that.And really there is no need to be confused with grammar ,specially because its basics is not difficult and you are very close to get a good grasp of it with your present knowledge, I can see it.
What you do when you analyse the sentence is breaking it into functional chunks. And there is not too many of this chunks,don't be confused with it. This chunks had to be labeled somehow( this labeling often make confusion since it is very often different for essentially the same concepts).
In the simple sentence like this you've posted,all you need to do is to find what is subject, verb, object(direct,indirect or prepositional),complement(subject or object)and what is adverbial(may be obligatory or non-obligatory).In order to do that you need to :
First : To understand the logic of this elements (i.e their semantic)- what every element do in the sentence, what is it,and what their form is. And it is simple as that.You only need to know about this elements individually. Be sure they exist to describe things not to make it complicate. And again,I repeat, you need to know that they may take different forms and form is a shape of some functional part of the sentence or phrase (e.g subject is most often a noun or a noun phrase,but it can be prepositional phrase as well,or a whole clause or adjective..you see the point?).
Second (but not less important):
You always need to make clear difference between the levels of analysis,and to remember that there always exist vertical hierarchy between the parts. When you have broken the sentence into chunks and found that "sisterly advice on the subject of girls" is the direct object, never forget that it is part of the sentence. Now you can analyse the direct object .What is it in this case (you ask yourself what is its form). Answer: It is a nominal phrase. Now you're analysing this nominal phrase as I've shown in my first post. And Susiedqq answered you that "of girls" modifies "subject" which means that you can analyse more:
i.e the postmodifier (on the subject of girls) in the noun phrase of higher level (sisterly advice on the subject of girls) is not a simple word but a prepositional phrase (preposition + noun complement).Now youre breaking it into chunks since the noun complement is not a simple word but a noun phrase in which the part "of girls" is postmodifier of the noun " subject" . And now you've reached the end of the analysis(if you dont want to dig into morphology and dissect words,which is also possible but seems totally unproductive

) i.e you've gotten bare words and now you can do the other way around if you want and climb from the single word to see how they build up higher functional units all the way to the sentence as the highest point which represents the building itself.
It was in brief about it ,but if it is not clear yet don't let yourself be confused and just find some good source to read about types of phrases (nominal, adjectival,adverbial,prepositional) and their construction and function. Then you can read a bit about clause types as the neighbour of phrases one level above and all will become clear to you I'm sure. You could find some sentence you have some doubts about,analyze it ,and post your findings here. I think it is a good way of learning also

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P.S If you like this one you can print it freely,and moreover I cede all copyright to you
