Questions & Answers about Onko tuo poika yhdeksäs vai neljäs?
How do I form ordinal numbers like yhdeksäs and neljäs?
In their basic form, most ordinal numbers from 1 to 10 are made by adding -s to the end of the normal number. For example, neljä (four) becomes neljäs (fourth).
Since the word for nine is yhdeksän, why is ninth yhdeksäs instead of yhdeksäns?
When a number ends in -n, like yhdeksän (nine) or kahdeksan (eight), that final -n drops off before you add the ordinal -s ending.
Why does this sentence use vai for the word or instead of tai?
Finnish uses vai specifically in questions where you are asking someone to choose between mutually exclusive options. Since the boy can only be ninth or fourth, you use vai. The word tai is mostly used in statements.
Why is the question ending -ko attached to the word on?
To form a question that doesn't use a question word like who or what, you attach the -ko ending to the main verb and move it to the front. Here, the verb on (is) gets the ending to become Onko (Is...?).