effectualness

The effectualness of the new policy was clear from the drop in complaints.

用法提示：这里 effectualness 是名词，意为“有效性”，作主语。

Researchers measured the effectualness of the treatment over a six-month period.

用法提示：effectualness 是名词，作动词 measured 的宾语，指效力。

Critics questioned the effectualness of the training program after the results were published.

用法提示：effectualness 是名词，作动词 questioned 的宾语。