Many educators provide step-by-step walkthroughs of the workbook exercises. These are particularly helpful for understanding the "why" behind the answers.
Communities like r/SGExams on Reddit often share tips on where to find the "Huodong Ben" (活动本) with answer keys. sec 1 chinese workbook answers link
If you are looking for specific vocabulary or concept breakdowns rather than just direct answers, these sites offer excellent PDF downloads: these sites offer excellent PDF downloads: