some question of punctuation

[enydia]

Hi, everyone.

I have some questions of punctuation.

1.
Should these phrases and abbreviations be followed by a comma: namely, that is (to say), for example, for instance, i.e., and e.g.? I found some different examples and was very confused. Such as:
The best pupil in the class, i.e. Peter, won the prize.
I like all fruits (i.e., I eat pretty much anything) .

2.
Someone told me that when being used in the middle of a sentence, etc. must be followed by a comma, but I found this example from Oxford Advanced Learner's Dictionary (OLAD, 4th edition):
have no, some, etc sympathy with sb/sth
Is it right?

3
I found that almost every i.e. is written as ie in OLAD (4th edition), which really confused me. Aomong ie, i.e, ie. and i.e., which is/are wrong?
And how about etc and etc.?

4
Should viz. be preceded and followed by commas?


5
Have I to separate the phrase involving 'such as' from other parts of a sentence? Among the following three sentences, which is right?
The Roman languages such as French, Italian are all derived from Latin.
The Roman languages such as French, Italian, are all derived from Latin.
The Roman languages, such as French, Italian, are all derived from Latin.

Thanks.

[Tdol]

GV Carey the author of Mind the Stop, a guide to punctuation, said that punctuation was guided 2/3s by rule and 1/3 by personal taste. If you look at this poll, you'll see that the majority of user agree with him on this site. This is a far wider scope for individual choice than in many areas of language; few would be so lenient in grammar. Therefore, with punctuation I would recommend not looking for rules that apply universally; different people punctuate differently.

There is a tendency nowadays towards simplifying punctuation, so more and more people use eg instead of e.g.. I would have put a comma in #2, and generally use commas with for instance, etc. In the last one, I would use such as French and Italian,.