Don't worry about this. You can say "I've bought a new game" in general, notice: in general About "a" or "the", you can find it easily on many pages, books. My simple idea: - When you talk about something the first time, you use "a" e.g. I have bought a new car today! - The next time of mentioning, you can use "the", or some similar words such as "that,..." e.g. The car is so shiny! ^^ or. That car is so shiny (suppose it's not here at the time of speaking)

kelvinho8, If you are not sure if the listener knows what you are talking about then use the indefinite article. Of the four possible situations below only one calls for the definite article. . *Matrix of Definiteness/Indefiniteness ..............................................Knows specifically what is being referred to? ...........................................Writer/speaker............................... Reader/listener the: Can I use the car? -----------Yes --------------------------------------Yes a: I saw a dog today. -------------Yes--------------------------------------- No a: I heard you wrote a book.------No------------------------------------- Yes a: I need to buy a new belt. -------No------------------------------------- No Reasons why a reader/listener is considered to know that a noun is specific. 1. The noun has been previously mentioned. I have a dog. The dog is brown. 2. A superlative or ranking The tallest girl in the class Do you see the third person on the left in this photograph? 3.The noun describes a unique person, place, or thing THE earth revolves around THE sun. 4. There is a defining clause or enough information to make the noun specific. Do you remember the student from Japan who was in our class last year? (If there was more than one student from Japan in that class then you would use "a".) 5. The context makes it clear that a noun is specific Turn off the light. Close the door. * adapted from Brown, R. A First Language. Cambridge, MA: Harvard University

You can use "a" in general case, like for the first time of talking about it. Then you can use "the" later.