1. In Renoir painting, we can see warm colors such as orange and yellow.

2. In Renoir painting, we can see warm colors like orange and yellow.

3. In Renoir painting, we can see warm colors for example orange and yellow.

4. In Renoir painting, we can see warm colors, for example orange and yellow.
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Q1: Are they all the same in meaning? In the last two sentnces, 'for example' is used. Do we have to put a comma before 'for example'?

Q2: How do you pronounce 'Renoir'?
Do we have to stress the first syllable or the second syllable?
I could see two stress patterns in the dictionary. Which one is commonly used?

2 answers

In all four sentences, "Renoir" needs to be in singular possessive form ~~> Renoir's

In sentences 3 and 4, you need a comma before and a comma after "for example" -- see Rule 2 here: http://data.grammarbook.com/blog/commas/commas-part-10/
Pronunciation --

http://www.dictionary.com/browse/renoir?s=t

Click on the little sound icon to hear his name pronounced. ren-WAHR