测试结果不确定，医生建议再做一次检查。

The test results were inconclusive, so the doctor recommended another examination.

inconclusive 是由否定前缀 in-（表示"不"）和形容词 conclusive（决定性的）组成的复合词。conclusive 来自动词 conclude（得出结论），加上后缀 -ive 构成形容词。 inconclusive 字面意思是"不能得出结论的"，引申为"不确定的、非决定性的"。