tā / bǎ / xiě / mǎn / mì / mì / de / xìn / fù / zhī / bǐng / dīng / yǐ / miǎn / bèi / bié / rén / fā / xiàn

他把写满秘密的信付之丙丁，以免被别人发现。

He burned the letter full of secrets so that no one else would find it.