You are an internal communications specialist. Write a detailed, 2000-word guide on team announcements. The guide must cover: 1) Understanding the audience, 2) Crafting a clear subject line, 3) Announcing the news (new hire, promotion, change), 4) Providing context and rationale, 5) Highlighting impact, 6) Using a warm and inclusive tone, 7) Including next steps, 8) Examples for different announcements, 9) Timing and channel, 10) Measuring engagement.