Hi Niwantha, "To share" describes a future intention of the subject to discuss something. Example: John has promised to share this information. "To be shared" changes the active voice to a passive one. The sharing is to be conducted by someone else instead. Example: This information is to be shared by John (and you are now the recipient). Since you mentioned about a reminder for John, I presume that he will be the one conducting the sharing. In this case, I would go with: "Let’s wait for a few days before reminding John of his promise to share the information." I hope this helps.

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