بَلْ أَصْلَحَ الْعُمَّالُ الْجِسْرَ، مَا هَدَمُوهُ.
Rather, the workers repaired the bridge; they did not demolish it.
If the listener firmly claimed that the workers demolished the bridge, the correction reverses that belief, giving the force of qasr al-qalb. If the listener imagined the action included an additional, irrelevant activity, excluding that alternative would instead resemble qasr al-ifrād.
The linguistic form may be similar across the two contexts. The distinction depends on whether the interlocutor holds the opposite assertion or combines the true assertion with another. An explicit account of the listener's belief is necessary.