- Why the use of s in seem_s_:
News is a collection of information on recent events. We cannot count how many is in the collection, so the noun news is uncountable. We don't say "8 news", "many news" or "I've got a news" because 8, many and a can be counted. What we do is:
Add a quantifier to make news countable and say: "8 articles of news"
Use much for uncountable nouns and say: "much news"
Omit "a" and say: "I've got news"
News has a plural ending (the s in news makes it appear plural; there is no "newses") and followed by a singular verb. Hence, "news seems" is correct.
- Is news both singular what and uncountable?
News is an uncountable noun that take singular verbs (new_s_ seems) and use singular forms of words such as this or that ("this news seems good", "that news was good").
- How can I tell if any other word follows the same conjugation?
I'm not quite sure what you mean here, but on the subject - verb agreement of words such as news,
" Uncountable nouns that have a plural ending (mathematics, academics, aerodynamics etc.) take a singular verb, so the verb is conjugated in the singular:
"Mathematics fascinates me."
"Mathematics has fascinated me."
Therefore, these types of words follow the same conjugation.
I hope this is helpful.