1. Express gratitude: First of all, you can express gratitude to your in-laws. You can say, "Thank you very much for coming today. I'm glad to have the opportunity to celebrate the children's engagement with you."
2. Praise your family: Then you can praise your in-laws. You can say, "I've heard about your fine traditions and beautiful family style, and I'm proud of your family."
3. Emphasize cooperation: You can say, "I believe our family will become a great team to support the children's future."
4. Blessing and blessing: Finally, you can express your blessing to your in-laws. You can say, "I wish your family happiness, health and peace, and look forward to the happy future of our two families."