12．承包人得被視為在投標前已對其工程標書，對標價的建築工程清單、單價和價格表（如果有）上所列的單價和價格的正確性和完善性感到滿意，此種投標價格必須貫穿其所有的契約義務，適用於所有為工程的正常施工和維護所必需的事物，除非本契約另有規定。然而，在施工期間，如承包人遇到除工地氣候之外的其他自然情況或人為阻礙，依他所見，此種自然情況或人為阻礙是經驗豐富的承包人也無法預見的，承包人必須立即書面通知工程師代表，如工程師確認此種情況或人為阻礙為經驗豐富的承包人無法合理預見，工程師必須作證且業主支付承包人由於此種情況而承擔的額外費用，包括因遇到此種情況或阻礙而：
（a）of complying with any instruction which the engineer may issue to the contractor in connection therewith，and
（1）為執行工程師可能向承包人發出的與此情況有關的任何指示而發生的正當合理的費用，以及
（b）of any proper and reasonable measures approved by the engineer which the contractor may take in the absence of specific instructions from the engineer．as a result of such conditions or obstructions being encountered．
（2）在無工程師具體指示時，承包人可能採取業經工程師認可的恰當和合理措施而發生的正當合理費用。
13．save insofar as it is legally or physically impossible，the contractor shall execute and maintain the works in strict accordance with the contract to the satisfaction of the engineer and shall comply with and adhere strictly to the engineer's instructions and directions on any matter whether mentioned in the contract or not，touching or concerning the works．the contractor shall take instructions and directions only from the engineer or，subject to the limitations referred to in clause 2 hereof，from the engineer's representative．
13．除因法律或自然因素而不能之外，承包人必須嚴格按契約規定施工和維護工程，使工程師感到滿意，且必須遵守和嚴格執行工程師有關任何事項的指令和指示，不管契約中是否有規定，提及或涉及到工程，承包人只能從工程師處接受指令和指示，或根據本契約第2條規定，接受工程師代表的指令和指示。
14．（1）within the time stated in part 11 of these conditions，the contractor shall，after the acceptance of his tender，submit to the engineer for his approval a program showing the order of procedure in which he proposes to carry out the works．the contractor shall，whenever required by the engineer or engineers’representative，also provide in writing for his information a general description of the arrangements and methods which the contractor proposes to adopt for the execution of the works．