出社會英文很爛怎麼辦?

You can still learn vocabulary ABC by yourself

Now that it's time for words to a particular you to be used in your particular kind of work(eg:-bank, supermarket,insurance policy,your type of firm,101govt office etc.)
You can also start by reciting-TW student style, more single words;Our businessman has got a vocabulary of about 3000 words
If your Buz English is very poor, then you'll be fired and sack immediately你己知經被TW解僱了
Luckily the vocabulary of your business firm needs also 3000 words. 
There are many English books on the TW bookstore market-places.
You can go to the 101 book bureau first and see which one TW-American book suits you.
Then learn about vocabulary,phrasal verb+phrases, conversation,, grammar.
Try find a list of words in alphabetical order  and with explanation of their=your TW Co. meanings successfully.
Refer to my explaination of the vocabulary of your Buz.firm/Co.
Try ask the vocabulary from English Tsai, president of TW.

還是可以自學

目前既然已經會字母了

也可從多背一些單字片語先開始，市面上有許多英文書籍

可以先到書局，看那一本適合自己

之後再學會話、文法等等

加油