Preliminary study on the mode of sea exploition 并列题名：Preliminary study on the mode of sea exploition Preliminary study on the molecular mechanism of soybean regeneration Preliminary study on writers' mindset and literary creation a preliminary study of trade routes in early mesopotamia 并列题名：Preliminary study on the molecular mechanism of soybean regeneration a preliminary study of China's industrial organization Preliminary study on the "New Normal" of China's economy a comparative study on the mode of social work education 并列题名：Preliminary study on writers' mindset and literary creation