are unions non profit organizations Economist lynde hull explained that the benefits of capital in different periods of time would be interest. According to linde hull, interest in a specific period and the difference between the expected consumption is savings (during the period of the growth of capital), and returns the sum of consumption and savings are given period of time. The withdrawal of shares shall include the two kinds of compensation for recovery and compensation. Free withdrawal refers to the return of shares that have been allocated for free. For example, shareholders voluntarily pay back their allocated shares voluntarily. "Buy" or "buy back" means a limited company shall buy back its shares from its shareholders at a certain price. The company's reduced corporate capital could affect the price of its shares in the market. Therefore, article 143 of the company law stipulates that the company shall not acquire shares in the company. However, the following situations are excluded: (1) reducing the company's registered capital; (2) merger with other companies holding shares of the company; (3) reward the employees of the company; (4) shareholders who have objected to the merger and separation of the company made by the shareholders' general meeting require the company to acquire its shares. Company for reduce the company's registered capital, and hold the company shares of other companies mergers and shares will be awarded to the company worker of acquisition, the company's share capital shall be subject to the resolution of the shareholders' general meeting. After acquiring the shares of the company, the company shall cancel the registered capital of the company within 10 days from the date of the acquisition; Belong to a merger with hold shares in other companies the company and the shareholders for the company merger, division of resolutions of the shareholders' general meeting to dissent, requiring companies to buy the shares, shall transfer or cancellation within 6 months. The company shall not exceed 5% of the total amount of the shares issued by the company for the company's purchase of the shares of the company by awarding the shares to its employees; As regards the financing source of the acquisition, the expenses shall be paid from the after-tax profits of the company; The shares acquired by the company shall be transferred to the staff within one year. 6. The accounting benefit is bound by the prudent principle. According to the principle of prudence, when there are a variety of accounting methods to choose from an economic business of an enterprise, it should choose a method that neither overestimates nor depreciates the benefits. Enterprises manipulate profits to achieve homogenization of profits, most of which adopt the method of overestimating earnings, and the subjective selection of the period of value-added. The market is the condition that Commodity Exchange is carried out smoothly, it is commodity circulation domain all Commodity Exchange activity total. The market system is made up of all kinds of professional market, such as goods and services market, financial market, labor market, technology market, information market, the real estate market, cultural market, a complete system of tourism market, etc. At the same time, each professional market in the market system has its special functions, which are interdependent and mutually restricted, and work together in the social economy.