Questions about example sentences with, and the definition and usage of "Ordinal"

The meaning of "Ordinal" in various phrases and sentences

Q: What does what are ordinal numbers mean?
A: 1 (one) - cardinal number
1st (first) - ordinal number

2(two) - 2nd (second)

etc.

Synonyms of "Ordinal" and their differences

Q: What is the difference between ordinal numbers and sequential numbers ?
A: would you be interested in talking with me to improve my English?

Translations of "Ordinal"

Q: How do you say this in English (US)? 1st, 2nd, 3rd, ...This is the ordinal numbers for usual numbers. Are there any ordinal forms of "some", "many" and words expressing undefined numbers?

e.g.
This is the first time I have eaten sushi.
This is the some-th time I have eaten sushi."??
A: We often talk about unknown/undefined numbers as "the n-th time" or "the x-th time".
"N-th" is easier to pronounce with the "th" sound, so it's more common as an ordinal. (The "n" stands for "number".)

...That "n" can then be used as a variable in a math equation.
Q: How do you say this in English (US)? what is the ordinal number of you among the children of your parents?
I am the third child of my parents
Is this question sound natural? please correct me.
A: What's your birth order? I'm the 3rd (child) in my family.
Q: How do you say this in English (US)? what is the ordinal number of Joe Biden among the president's of USA?
He is the 46th president of the United States.
Is the question I given is right?
A:
Thank You
If the answer is I am the fourth son of my parents, then how to ask the question to get this answer?
Q: How do you say this in English (US)? 100 in ordinal number
A: The one-hundredth (the second « d » is silent)

Q: When do ordinal numbers not need the article “the” before them?
A: We use THE plus the ordinal numbers when it comes before a noun.

This is THE fourth time I’ve ridden a horse.
THE first man in line was an elderly gentleman.

Q: ordinal numbers from 1 to 20 please tell me if I wrote them correctly or not.
1st first
2nd second
3rd third
4th fourth
5th fifth
6th sixth
7th seventh
8th eighth
9th ninth
10th tenth
11th eleventh
12th twelfth
13th thirteenth
14th fourteenth
15th fifteenth
16th sixteenth
17th seventeenth
18th eighteenth
19th nineteenth
20th twentieth

A: Yes.
Q: They (ordinal numbers) are used mainly in the singular, although there exist special forms for plural nouns, of which only pierwsi and drudzy are used much. Does this sound natural?
A: The one thing I'd suggest as a change _in writing_ is to put "pierwsi" and "drudzy" in quotation marks. But that's purely a punctuation thing, so I still rated the English part of it all as perfectly natural. Bookish, but natural. (For example, "exist" would probably become "are" in most people's speech, and "of which" might become "and even as to them.")
Q: ordinal numbers good or bad ? Does this sound natural?
A: Muito bom! Parabéns!
Mas acho que "fourth" não soa natural.

Aqui está um audio com um exemplo:
"That was the fourth book I've read this month."
Q: How is "a [ordinal number]" possible?
e.g. "China's yuan currency falls for a second day" on http://www.bbc.com/news/business-33875061, why not "the" second?
A: 'The' would also be correct here. Using 'a' here puts a tiny bit more focus on 'yuan currency falls' rather than 'second day.' Using 'the' would put more focus on the fact that it is the second day. The nuance is very slight, and it is a choice of style.

ordinal

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