If I were in your position, I'd go for apartment and movie. These are standard American terms, but they're also used worldwide by most other English speakers. Sneakers and subway are less common outside the US, but they're still universally understood. I definitely wouldn't use "tube" - that's an informal name for the London underground. Here's a fact. If you refer to your home in Japan as an "apartment" or your shoes as "sneakers", it will sound fine to a British person. We wouldn't bat an eyelid. English speakers from Canada, the UK, Ireland, Australia, NZ, SA and the Caribbean are all essentially bilingual when it comes to receptive skills. We have been exposed to so much American English in the media that we're barely even aware of it. We wouldn't necessarily call our shoes "sneakers" or talk about "going to the movies", but we wouldn't really notice if we met another person who did use these terms. We hear them all the time. The reverse is not necessarily true. The language environment of most Americans is predominantly American. So a US English speaker who heard you say "flat" would understand you, but they would also probably think, "Huh? Flat? That's kinda weird. Why's this Japanese guy talking like a Brit?" If in doubt, use the American term - - it's probably your simplest option.

Hi Judy, sorry for the late thank you for your answer.I like it!

Apartment !

I guess it depends on whether you are learning British or American English. Also if you are using it in a job, or you speak mostly to Americans or to British people that could influence your choice. More people speak American English, also Canadian English is very similar to American English. I am American and can rarely tell if someone is from here or Canada. Sometimes if they are from certain parts of Canada I know they are Canadian. It is really just a matter of choice. We never say flat for apartment here, nor trainer for sneaker, however, we say film or move, and we never say tube or underground, just subway and in New York they say train for both the one under and on the ground.