However, the passive voice is useful when you do not want to call attention to the doer. The doer may be obvious or unimportant. Try to avoid long sentences. A rough guideline is to avoid sentences longer than 40 words. It is usually more clear to break long sentences into 2 shorter sentences.
Short sentences are useful to make important points or conclusions.
Use parallel constructions When you have a series of words, phrases and clauses, they should be put in a parallel or similar form. This allows the reader to identify the relationship between them more clearly. This sentence has good parallel construction. Avoid long strings of nouns. Use the verb form in preference to the noun form.