In an environment with only one type of financial asset，a multi-period market trading model is pro-posed，which contains three types of participants． This model explores the impacts of the informed trader proportion，expectation precision，nature of information ( good or bad) ，market sentiment，trader initial asset，short-selling constraint and risk attitudes on financial market dynamics． It is found that the change in the proportion of the informed traders and that in the expectation precision are the subjective and objective reasons for market price reversal phenomenon，respectively and that these subjective and objective factors have different effects on the market dynamics． Above all，this paper also provides some theoretical explanations for the phenomena of fluctuation，mean reversion，bubbles of market price，price under reaction，over reactions，and so on．