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![Ronald Greer](https://uploads.teamtreehouse.com/production/profile-photos/9063362/micro_rsz_img_1472.jpg)
Ronald Greer
Front End Web Development Techdegree Graduate 56,430 PointsHow come it asks me to type in two type parameters and when I do I get the question wrong
The question asks me to type to basic type parameters and it keeps giving me errors: class Pair <T1, T2> { }
1 Answer
![Lauren Moineau](https://secure.gravatar.com/avatar/85610a2dbe7e46c1f8069977ed981d5b?s=96&d=https%3A%2F%2Fecs-static.teamtreehouse.com%2Fassets%2Fcontent%2Fdefault_avatar-445fbbabfc8dc9188fb5967fe43322ee0c3e0dd1e10f378bf8343784af5a13eb.webp&r=pg)
Lauren Moineau
9,483 PointsHi Ronald. Because they want you to use a single uppercase letter, as per the naming convention for generics' type parameters. You can check the Oracle documentation here.
Hope that helps :)