The development of Industry 4.0, smart contract is one of critical application in the blockchain platform, which is the remove of intermediary services to facilitate transactions directly between stakeholders, in which the trust between stakeholders is guaranteed by a blockchain system. However, existing solution of automated execution of smart contract is simply given by the prescribed program code. This solution results in two negative effects: the contract is not human-readable and difficult to modify; contracting parties cannot collaboratively draft the contract and cannot assure the shared consent of the contract. Therefore, we will introduce a brand-new solution of smart contract, called Intelligible Description Language Contract (IDLC). It will allow contracting parties to draft a contract collaboratively just as working on text editor with a supportive tool of concept disambiguation through Supervised Sentence Contract (SSC). SSC consists of Machine Natural language (MNL) via Semantic input method (SIM). SIM provides a method of supervised contract obligation creation. MNL provides the capability of universal computer-understandability. Meanwhile, in the complex contract transactions and management, especially in supply chain management, a chained evidence sequence is designed to avoid collusion. IDLC is a first paradigm that bridges the traditional contract based on natural languages and the smart contract based on blockchain platform.