shenyumen8800

with the economy developing,human  need resource more and more widely,the resource of landing don't satisfy the human's demand,therefore, human start to exploit the resource of the sea, because the sea is very widely and deeply,human don't  konw the secret of the sea'
at the same time,human don't have the advanced technique for the deeply resource of the deeply sea,so human acquire the resource of the deeply sea  very  slowly.