At times, I have heard: “I’ve been working here from 2015.”
Actually it should be: “I’ve been working here since 2015.”
Or one can say: “I’ve been working here for two years.”
Here is how since and for are used:
since + point in time (since 1906)
for + period of time (for 10 years)
We do use from with time expressions, but in a different sense. Here are some examples:
The conference starts from tomorrow.
The shop is open from 9:00 am to 5:00 pm.
And yes, by now you know why the ad is correct: Trusted since 1906.
In fact, from now on, you know the difference between since and for.
This is a commonly used idiom: he has a chip on his shoulder. Some people use it to indicate that he is behaving arrogantly, normally due to his success or position. Perhaps they are making a connection between the chip on his shoulder and a microprocessor chip or a blue chip stock. Actually, this is not the meaning of the idiom. It is not related to being arrogant.
When someone has a chip on his shoulder, he is angry or feels disrespected. And he feels angry/disrespected because he is under the impression that he has been treated unfairly in the past.
And that is what it means to have a chip on one’s shoulder.
A venture capitalist once said that he looks for an entrepreneur who has a chip on her shoulder, as this means that she will try even harder to succeed. Does that make sense?