Fill in the blank with the most appropriate verb to complete the sentence correctly: We should give everyone training in citizenship, but we have ____________ this aspect till now.

Introduction / Context:
This question focuses on choosing the right verb to describe how society or institutions have treated the important aspect of training in citizenship. The sentence contrasts what we should do in an ideal situation with what we have actually done so far, so the verb must reflect failure or omission, not direct refusal or prohibition.

Given Data / Assumptions:

• Training in citizenship is something desirable and necessary.
• The speaker believes we should give this training to everyone.
• However, up to now, this aspect has not received enough attention.
• The verb must express the idea of ignoring or not paying proper attention.

Concept / Approach:
We need to distinguish between “neglecting” something (failing to care for or pay attention to it) and actively refusing, denying, or disallowing something. Here the focus is not on forbidding training in citizenship, but on failing to provide it, which points toward the word “neglected”.

Step-by-Step Solution:
Read the first clause: “We should give everyone training in citizenship”. This is clearly positive.The second clause must show that we have not done what we should.“Denied this aspect” would suggest refusing someone a right or benefit; that is not the exact idea.“Refused this aspect” implies an active rejection, which is too strong.“Disallowed this aspect” suggests formally prohibiting it, usually through rules or law.“Neglected this aspect” precisely means we have ignored or failed to give attention to it, which matches the context.

Verification / Alternative check:
The complete sentence with the correct option reads: “We should give everyone training in citizenship, but we have neglected this aspect till now.” This sounds natural and clearly expresses that the aspect of citizenship training has been overlooked rather than formally forbidden.

Why Other Options Are Wrong:
“Denied” and “refused” both imply a conscious and active decision to withhold something. “Disallowed” implies a rule or prohibition. The sentence, however, hints at carelessness or lack of focus, not at strict banning or deliberate refusal. Therefore these three options do not capture the intended meaning.

Common Pitfalls:
Many learners confuse “neglect” with “refuse” or “deny”. Remember that “neglect” is about failing to do something that you ought to do, often due to carelessness, whereas “refuse” and “deny” involve a clear decision not to allow or accept something.

Final Answer:
The correct verb to fill the blank is neglected.