i think ,neither cet4 nor cet6 could mean anything. it is just a barren certificate
which can encourage you to learn sth. more. all that you can obtain from this
certificate is only sth called "confidence". nevertheless, that is enough.
if you want to learn something more: for commercial english ,you should
go ahead with further study in this aspect.
as to oral english ,you can improve it by taking part in the english corner.
Sb. always imagine that she/he will find a bf /gf in english corner. i really consent to that kind of thought.
at first you will meet sb. who will always be flirtatious with you . and you can easily establish a rapport with him. then the flowers of love can be cultivated by your wholehearted communication.
if you want to be an interpreter, that will be more demanding. to be competent with that post,you should do a lot of hard work .
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my opinion above is so superficial . please point out my mistakes.
criticism is welcome as well.