I told you I promised my good Fairy to behave myself, and I am going to keep my word.

我跟你说过，我答应过我的好仙女要规规矩矩的，我一定会遵守诺言的。

youdao

When I tell someone I will not betray his confidence I keep my word.

当我对人说我不会辜负他的信任时，我会说到做到。

《柯林斯英汉双解大词典》

Please believe me. I'll keep my word.

请相信我，我决不食言。

youdao

In less than a week the word was out that my distribution company would do anything to keep a customer happy.

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