what does "for" meaning in "We'll have a meeting for Monday"? why don't they use "on monday" instead? please help me find it out!

"it's called a/the...?" help me find it out! thank you!

what does "I need for you to come" mean? what's the difference between "I need you to come" and "I need for you to come"?

what does "Commodities market" mean? what's the difference between "Commodity markets" and "Commodities markets" "Commodity prices" and "Commodities prices"?

what does "attempts was" mean? "attempts" is plural but in a movie, they said: "Europeans' attempts was met with rebellion" It must have had some meaning! please help me figure it out! Thanks!