Ответы
1). Present simple - Chinese people discover gunpowder
2). Present continuous - Chinese people are discovering gunpowder
3). Present perfect - Chinese people have discovered gunpowder
4). Present perfect continuous - Chinese people have been discovering gunpowder
5). Past simple - Chinese people discovered gunpowder
6). Past continuous - Chinese people were discovering gunpowder
7). Past perfect - Chinese people had discovered gunpowder
8). Past perfect continuous - Chinese people had been discovering gunpowder
9). Future simple - Chinese people will discover gunpowder
10). Future continuous - Chinese people will be discovering gunpowder
11). Future perfect - Chinese people will have discovered gunpowder
12). Future perfect continuous - Chinese people will have been discovering gunpowder