Adjective, pronoun and numeral in Old German and Roman languages

Cardinal numbers

Cardinal numbers are the type of number that are used to count and enumerate things, like "one", "two", and "three" in Modern English, as in "there are three pigs".
Cardinal numbers in Old English could either be declined adjectivally in declension agreement with whatever they were referring to, or treated like a noun which would be followed by the genitive plural of whatever they were referring to. The Old English words for 1, 2, and 3 were always treated in the former manner - like an adjective that modified a noun or a pronoun.

Cardinal numbers 4-19

The words for 4 through to 19 were normally not declined when used like an adjective, but when used as a substantive (meaningful lexicon like a subject) they were usually declined like a strong noun, according to their gender and case.
The words for these numbers are:

Ordinal numbers

Ordinal numbers are numbers that are used to rank things in a particular order, like Modern English "first", "second", and "third". All ordinal number forms were always declined like the weak adjectival declension, except for the word "ōðer" - "second", which was always declined like the strong adjectival declension.
In Modern English, for most numbers, we just add the suffix "-th" to the cardinal form of the number to form an ordinal, as in "nine" - "ninth". Similarly, in Old English, the normal basic suffix to form ordinal forms from cardinal numbers was '-þa', but sometimes it varied slightly.

References

• https://oldenglish.info/adj5.html
• https://people.umass.edu/sharris/in/gram/GrammarBook/GramPersPronouns.html#:~:text=There%20are%20three%20persons%20for,they%20function%20in%20a%20sentence.
• https://zims-en.kiwix.campusafrica.gos.orange.com/wikibooks_en_all_maxi/A/Old_English/Numbers