影视英语口语:说话算话

“说话算话”在英语口语里能怎么说？

初级口语：you promised
地道口语：cross your hear

影视来源：奥斯卡热门《飞屋环游记》
剧情引导：沉默寡言的小男孩卡尔无疑遇见火爆性子的小姑娘艾丽，却不幸手臂骨折。夜里艾丽偷跑到卡尔的房间来探望他，顺便向他展示自己的南美冒险之梦......

When I get big, I'm going where he's going, South America. It's like America, but south. Wanna know where I'm gonna live? "Paradise Falls, a land lost in time." I ripped this right out of a library book. I'm gonna move my clubhouse there and park it right next to the falls. Who knows what lives up there. And once I get there? Well, I'm saving these pages for all the adventures I'm gonna have. Only I just don't know how I'm gonna get to Paradise Falls. That's it! You can take us there in a blimp! Swear you'll take us! Cross your heart! Cross it! Cross your heart! Good, you promised. No backing out.