Mainly talk about {enterprise law}, {economic contract law}, {contract law} and the corresponding business knowledge of the company's products or services, and also know the accounting knowledge.

If it is a buying and selling enterprise, we should pay attention to the subject matter, price, payment method and liability of both parties in the contract (penalty method for breach of contract). If there is an installation agreement, it is necessary to stipulate the location, content and degree of installation, and mark the installation boundary with drawings when necessary to avoid doing the work that should not be done, and the work that should be done has not been done.