Alternations for the four two-argument predicates.

The maximum number possible is 42. Data is given for the full BioIE corpus. The column labelled tokens shows the number of tokens for which no argument was labelled “can't tell.” The column labelled X shows the number of tokens with at least one argument labelled “can't tell.”最大可能取值为42。所有数据均来自完整的BioIE语料库。标记为tokens（Token）的列，展示了未被标注任何论元为‘无法确定’的Token的数量。标记为X的列，展示了存在至少一个论元被标注为‘无法确定’的Token的数量。