Therefore,it is significant to explore the illocutionary act reflected by modal verbs,based on the Speech Act Theory,in order to clarify their semantic and pragmatic functions in business contracts.

• 因此,以"言语行为理论"作为理论框架,探讨情态动词所能实现的各种言外行为,以明确情态动词在商务合同中的语义及语用功能是十分必要的。