I worked, I've worked, I have been working. I need some clarifications

Question

Could you help me with these sentences:

1. I lied to her. (I'm just making a statment)
2. I've lied to her because the truth would have hurted her.

Second example:

1. I have been working at Google for 10years. (Meaning I am still working there)
2. I've worked at Google and it was nice.(I don't work anymore)
3. I worked at Google. (Not sure about the difference with the previous one)

I'm learning the different tenses and it isn't so easy for me. Any help would be welcome.

Regards,

Answer 1

In each case, it's the context that determines the most suitable tense.

I have been working at ....

means, as you state, that you are still working at.... It stretches from a point in the past and continues into the present.

I have worked at.....

is the response that you would give, for example, if you were asked what experience you had in your field. Because this experience covers the period up to the present day, you might respond:

As well as obtaining a PhD in software development, I have worked at Google (for ten years) and have completed two years with Microsoft.

This tense stretches from a point in the past up to the present, without the implication that it is continuing.

I worked at.....

is a statement of something you did at some undefined time in the past and which you no longer do. You would use the past tense if you were asked, for example, where you had worked after leaving university. You might reply:

I worked at Google for ten years (before I went freelance).

Answer 2

You can use either. (I lied to her - simple past, I have lied to her - present perfect)

Second Example: There is little difference in meaning (1 and 2)

1. I have been working at Google for 10years. (I am still working)

2. I have worked at Google for 10years. (I am still working)

3. I worked at Google. (I no longer work)