learning written English is more important than learning ora

for learning the history,
we learn a lot about the ancient by the writen files reserved instead of tell-tale legend because what is written is more reliable and convincing then oral.
for the important business
we make "written" contract to bond the two sides to carry out their respective duties.
for the not so important business,people can keep themselves responsible as their oral promises.

你英文写作很好但口语不行，碰到老外囧了。