1. 没表情的：unexplained 未解释的 | unexpressive 没表情的 | unfair 不公平的
2. 未能表达原意的：unexpressed /未表达的/ | unexpressive /未能表达原意的/ | unfading /不褪色的/不凋萎的/不衰的/
adj
1. deliberately impassive in manner
e.g. deadpan humor
his face remained expressionless as the verdict was read