中文摘要：

在单时期模型和企业投资决策中的实物期权思想的基础上构建的两时期模型，证明了短期债务其实有可能使得企业发生过度投资行为，短期债务也有可能使得企业发生投资不足行为，长期债务总是导致企业发生投资不足行为，短期债务对企业投资不足的影响较长期债务要轻，以及平均债务期限与企业投资呈负向关系等重要结论。

英文摘要：

This paper constructs double temporal model on the basis of single temporal model and real options in corporate investment decision in order to prove that the short-term debt is likely to lead to overinvestment or underinvestment by enterprises, that long-term debt always results in anderinvestment by enterprises, that short-term debt is less likely than longterm debt to induce underinvestment. and that the average debt maturity is negatively related to corporate investment.