Help related with Grammar and Stylistic improvement is needed.

Dear people,

Will you be so kind to help me?
The below mentioned questions may sound funny for Native Speakers, but if you have time will you be so kind to help a little with grammar, stylistic and other matters related with English as I am working over English improvement 2 hours per day and project to master it in the best manner possible for Non Native Speaker.

1. Which one of the sentences sited below is right (a), grammatically wrong (b) and stylistically unsound (d)?

These phenomena also can be observed in the carbon tubes.
These phenomena can also be observed in the carbon tubes.
These phenomena can be also observed in the carbon tubes.

2. Definite article:

As far as I know the first sentence is correct

(1) The approximation is correct for the fermions and bosons.
(2) The approximation is correct for the fermions and the bosons.

But is that true that when one counts long list of items (meaning of which is clarified with auxiliary phrases) the definite article is needed (the IR field orientated detectors, the automated NO gas sensors, the chemical sensors and the photo detectors based on the wide band gap semiconductors)?

3. Can you advise a good site where I can download for free high quality audio materials on advanced British English?

Thank you all in advance,

Hayk

I want to draw your attention to the above-mentioned questions [and later I am planning to add some more (hope they will be interesting)], which site specific errors very common for many Non-Native Speakers (NNS).

Besides I have not yet seen a good grammar book written for NNS, where serious efforts to improve the stylistic of English language of NNS are made, e.g. by detailed exemplification of the patters of the common errors. If anybody can advise me any I will highly appreciate that.

E.g. I love very much the following books:

English as a Foreign Language, Grammar and Syntax For Teachers and Advanced Students by R.A. Close, British Council Representative, Athens, Harvard University Press, Cambridge, Massachusetts, 1963.

Guide to Patterns and Usage in English, by A.S. Hornby, Oxford University Press, Second Edition, 1975.

Sometimes the old solid academic books are better than oversimplified contemporary materials as the commercial aims to cover vast auditorium incline many scholars to lover the standards. Many try to avoid usage of complex brilliant sentences (full with substance and spirit of the language), some cut the vocabulary and actually sacrifice the academic quality of the substance at the altar of the simplified methodology, thus meeting the market demands. That diminishes the key marvel of the English language, which is reach not only by structural beauty, coherence and uniformity but by the magnanimity of ideas ever expressed on it.