Exercício: Qual frase é correta?

Which phrase is correct? Please, explain the errors!

I have already been working for the company during 5 years.
I had already been working for the company for 5 years.

Thanks!!
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Avatar do usuário Ricardo F. Bernardi 8810 16 163
You should read:

(1) https://www.englishexperts.com.br/forum/while-x-during-x-for-t1841.html
(2) http://www.teclasap.com.br/gramatica-while-during-e-for/

Following the previous statements, I believe the correct sentence is: I had already been working for the company for 5 years.

The Past Perfect Continuous is used to emphasize the repetition or duration of an action in the past prior to the other action also in the past.

The Present Perfect Continuous is used to talk about an activity that began in the past and continues to the present, emphasizing the duration or intensity of the action. In this case, to express the time, we usually use the words: since, for, all day, all morning, all week, etc.

During is used to say when something happens; for is used to say how long it lasts.

Both prepositions, during and in can be used to say that something happens inside a particular period of time.

Example:

We will be on holiday during the summer or We will be on holiday in the summer.
I woke up during the night. or I woke up in the night.

When we are talking about the whole of the period we use during, not in.