The pattern works smoother if you begin the 2nd clause with "they do so", or "they are so". 1. When they carry out the duty, they "do so" reluctantly. 1a. When they carry out the duty, they "do so" enthusiastically. 2. When those provisions are approved, "they are so", but not necessarily "implicitly". Hope that helps. Have a good day.

The sentences you provided are almost grammatically correct, but they could be improved for clarity and fluency. Here are revised versions: When they carry out the duty, they do so not necessarily "reluctantly." When those provisions are approved, they are not necessarily approved "implicitly." These revisions maintain the structure you used but make the sentences flow more smoothly.