Excellent explanation!! I enjoyed and learnt by reading it.
Are you an English teacher??

Best regards

I am terrible at grammar. However, I wanted to find an answer to your question because it is important to me as well.

Let’s start.

Your question about the word “Of” in Lucy’s sentence “Of those students who began repayment in 2005, 41% became delinquent (behind in their payment) or defaulted (could not repay a loan at all) within five years”.

Lucy was talking about those students who began repayment in 2005, she was not talking about any other students who began repayment in any other years.

We can rephrase Lucy’s sentence as:

41% of the students who had started their repayment in 2005 became delinquent or defaulted within five years.

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In the “englishforums.com”
Someone said:
‘of’ means something like ‘among’ I’d say.
Of all the friends I have = Among all the friends I have

So we can also rephrase Lucy’s sentence as: “Among those students who began repayment in 2005, 41% became delinquent or defaulted within five years”.

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In ”en.wikibooks.org”’s wiki/English_in_Use” you will find “Prepositions, Conjunctions, and Interjections” in which it says:

Of—Out from; proceeding from; belonging to; relating to; concerning; about; belonging to; connected with; indicating origin, source, descent, possession or ownership, relation of subject to attribute, material, part, source of a purpose or action, distance in space or time, identity or equivalence, agent, or passage from one state to another.

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Some more reading for you if you have time:

In “usingenglish.com” someone asked a question: “Can I start a sentence with “Of”?”

Someone answered:
“What you are listing are dependent clauses that begin with a conjunction.

The typical word order would be:
“conjunction and its clause,” “main clause.”

Using the dependent clause to start the sentence gives variety to writing and sustains interest. It’s boring to read too many plain declarative simple sentences in a row, but variation in sentence structure brightens up reading.

On the other hand, too frequent a use of this device is tiresome”.

And, an sample sentence was given as: “Of all the levels I have mastered while gaming, this one is the most exciting.”

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The littlest word is the hardest word.

Thank you for helping me learn more every day.

Betty

All the morning thinking about your two phrases:

“I could not believe it when I found that an article in my exam past paper was co-written by you”.

(I could not believed it when I found that an article was co-written by you in my exam)….mine

” I could not believe my eyes when I saw that an article in my exam past paper was co-written by you”.

(I could not believed my eyes when I saw that in my exam there was an article co-written by you)…mine
——-
Of course dear friend, the two are perfectly well written and absolutely understandable but as a
challenge I would like to twist them and write the idea in other way.
The last word is in the mind of the specialist linguist teacher, not in our skill.

Nice play Betty, I like it absolutely.

Greetings, emiliano

meme, are you pretty certain you were not telling a false story ?
90% unemployment rates in Palestine???
and $440400 in some privete university for only one semester??
oh, my gosh. I never thought of as the mountain of money as this..
you really scared the heck out of me!!!
you know, it was far beyond my expectation.
oh, no, where and how am I able to get such plenty of wealth to afford the huge schoolings??

Here She is the Saint Patron of the blind people.
It was the most popular name in Spain in the year 2006
…….

Saint Lucy enjoys very popularity in Scandinavian´s countries
the feast is December 13rd and on that date begins the feasts
of Christmas.
The Saint could be so popular as her name´s meaning is
light, so in these countries Sun Light is quite important, in
fact since December 13rd the Sun lights begins to longer
till the summer time.
……
Lucid = Lucido (in Spanish is p.p. of the verb Lucir)
Lucir as a verb, comes from the latin “lucere” that means …to give light
The Sun gives light,……Luce el Sol, because it gives light to the world

To be lucid also means “to have a clear transparent mind”
to recover from unconsciousness but also to have incredible
good reasons and clear thoughts.
He or she is a lucid man.
In psychiatry of or relating to a period of normality between periods of insane or irresponsible behaviour
its said that the person has regained (recovered) his or her lucidity.

Our dear teacher has one of the most beautiful names in English and in Spanish.
In russian is Svetlana and in Frech is Lucie, but also in German could be Lucia..
and so forth.
…….

Betty
It is possible you could read something like this once we were talking
about names and Lucy´s name and its meaning was one of the
subjects either.

But in other Arabic country like UAE (United Arab Emirate) the tuition cost a lot in private university i think for 1 semester u have to pay 120000 Drham emaraty
(440400 $) in some privete university and public university is just 4 native people and its free for poor people (native) but not cost much. As for the immigrant or emigrant have no place for them in their
public university so they sign privet University

In my previous post, instead of saying: “I could not believe it when I found that an article in my exam past paper was co-written by you”.

I should have said: ” I could not believe my eyes when I saw that an article in my exam past paper was co-written by you”.

Perhaps it is acceptable to use both?

At first I thought, no, this word is too difficult for me to remember.

Well, look up the dictionary anyway to find out what it means.

It says “Adj.1. lucid – (of language) transparently clear; easily understandable”.

Now I remember someone wrote something about Lucy’s name before. Could it be about the word “lucid” as well?

I think I will remember this word very well from now on.

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BTW, Dear Lucy, I could not believe it when I found that an article in my exam past paper was co-written by you.

The article was published in Summer 1996, and it was entitled: “Bringing Books into the Classroom: First Steps in Turning College-Level ESL Students into Readers”. A very well written article, thank you.

Thank you for reading my post and for being so considerate. I enjoyed reading your comment about my post, and, no, I will not be unhappy at all. It is a very healthy constructive advice to me, after all.

I hope I have not upset anyone who perchance read my silly little message. Lucy is the last person I want to upset. Hopefully she understands that I was always joking and was just trying to practice my English writing. It was not intended to cause any harm to anyone.

Yes, you are absolutely right, Elvis Johnny, I should at least say something to show my sympathy to those people who turned up to protest in the occupy movement.

On the other hand, I actually do not know enough to comment on this matter.

Look forward to reading more of your post.

All the best wishes to you.

Betty