*You are working at Starbucks, aren't you? Which location? (This one's fine.) *I have to leave at 4:30 because I'm gonna help my new house mate to carry her languages. (Only use "gonna" in an informal setting, like speaking between friends. Otherwise, if you're writing or speaking, use the formal "going to." Also, instead of "languages," I think you mean "luggage." Some "languages" are English, Japanese, Chinese, and Korean. "Luggage" refers to suitcases you use when travelling.) *My previous house mate, she left last week. (The organization is a little weird. Try: "My previous house mate left last week." It flows better!) She's going to get marry with Canadian. They have been with just 3 months! I can't believe it! (In English, we say someone gets "married to" someone else, so the first sentence would say, "She's going to get married to a Canadian." The next sentence would be, "They have just been together for 3 months!" The third sentence is fine.) And she already met his families and he already talked with her families on Skype! (English uses something called a singular noun when talking about "family." Even though there are multiple family members in one family, the word "family" in English is singular, not plural. The corrected version looks like this: "And she already met his family, and he already talked with her family on Skype!") Is it possible? (Yes, and your grammar here is fine too.) *I applied a job because one of my friend introduced me the job. ("I applied to a job because one of my friends introduced the job to me." or "...introduced me to the job.") But I'm not sure if I'll work there or not because most employees are Japanese. ("But I'm not sure if I'll work there because most of the employees are Japanese.") I don't want to speak Japanese too much. Of course the custermors are native speaker, but if I work there, I would speak Japanese with the employees. (Only the second one needs correcting: "Of course the customers are native speakers...")