There are a lot of meanings for each! Here are the most common uses and some examples. IN: Being physically inside a location or space: "The book is in the box." "I am in the building" Being inside something abstract: "I can't explain it in English." "It is hot in the summer." Within a certain period of time: "I will go there in ten minutes." Other words that are like IN are WITHIN, INSIDE, or INTO ON: On top of (encima de) "Put the blanket on the baby" "There are leaves on the ground." Where something is located "I have dirt on my face" "My house is on this street" How something is conveyed "I'm talking on the phone" "The game is on TV" An occurrence (usually a day of the week or a date) "We went on Sunday" "The party is on June 14" An appliance that is being used "The lights are on." "I turned the TV on" Other words/phrases that are like ON are ON TOP OF, UPON AT: Specific location "I am at the park." "I am at school." A certain time of an occurrence "The party is at 1:00." "We read at night." Direction "She is looking at me." "I throw the ball at the target." I hope this helps!

I agree with the answer above. "Cause" in this sentence is a verb. (It can also be a noun). "Because" is a conjunction - it joins two parts of a sentence together. 'Cause' as a verb: Dangerous driving can cause an accident. 'Cause' as a noun: They didn't know the cause of the illness. 'Because' as a conjunction: They didn't go to the park because it was raining.

The answer above explains it well. One, three, and five are correct. Two and four are incorrect.

This sentence means he stopped talking about that topic very quickly. That phrase references a game called "hot potato" that kids sometimes play - they stand in a circle and pass around a potato (or other round object) as quickly as they can. That's probably why they used "hot potato" and not some other vegetable. Hope that helps!