The phrase "brought to a standstill" denotes a situation where there is a complete stoppage or halt in the functioning of something. On the contrary, some common antonyms of this phrase are "free-flowing," "moving," "progressing," "working," and "functioning." These words indicate a state of things where there is smooth and uninterrupted movement, progress, or operation. For instance, a "free-flowing traffic" refers to a smooth and uninterrupted movement of vehicles on a road, while a "working economy" indicates a state where the economy is functioning normally without any serious disruptions. In essence, these antonyms convey the opposite meaning of "brought to a standstill" and suggest an active and ongoing state of affairs.