Comma before "and" which is being used after a list of items containing other and/s [duplicate]
Solution 1:
Your question isn't about a list of items.
The second 'and' does not add an item to a list. Instead it joins two phrases:
- certainly go to university with a more motivated and mature attitude
- contribute to its multicultural environment
Each of these phrases contains a verb and an object. (The 'will' part of each verb is extracted out to the beginning, which makes the phrases a bit less obvious.)
I contend that you would make it easier to read, and include a pause for reading aloud, by following the convention of adding a comma between phrases, so include the comma before "and contribute."
You have a list of two adjectives earlier in the sentence: the adjectives are motivated and mature. As there are only two items, never use an Oxford comma (also known as a serial comma.)
You might prefer to write the sentence as two clauses, so you repeat the subject, and you make the logic more clear. This may make it easier to make a judgement about the comma.
I will certainly go to university with a more motivated and mature attitude, and I will contribute to its multicultural environment.
Solution 2:
The sample sentence:
I will certainly go to university with a more motivated and mature attitude and contribute to its multicultural environment.
In this case, there is no valid use of the Oxford comma because there is no list (there are only two items and the Oxford comma is relevant at 3+ items). Inserting a comma before the bold and would be a comma splice error, which is itself a style discussion; different people have different tolerances and this fits in the gray area.
If the preceding clause were a list (3+ items), regardless of whether it uses the Oxford comma, things change:
I will certainly go to university with a more motivated, open-minded[,] and mature attitude, and contribute to its multicultural environment.
This is because the clauses are now more independent, so the comma splice is more permissible, though I'd still consider it awkward. Here is a better phrasing of that version of the sentence, which also works fine without the extra word I added to create the list:
I will certainly go to university with a more motivated[, open-minded] and mature attitude, and I will contribute to its multicultural environment.