1、His alibi for the night of the crime was dubitable, as there were no witnesses to support his claim.
他对于犯罪之夜的不在场证明是可疑的，因为没有证人能够支持他的说法。
2、The scientific findings presented in the research paper are dubitable and require further investigation.
这篇科研论文中提出的科学发现是值得怀疑的，需要进一步的调查研究。