Introductions of academic manuscripts are usually written in a specific-general structure.
Be very careful when using pronouns; likewise, avoid synonyms for key words — the reader may not know what the pronoun or synonym refers to.
Do everything you can to reduce redundancy (words, sentences, paragraphs, and even sections).
Use the passive voice rather than the active voice in your paper.
Some key words in previous sentences or paragraphs should be repeated constantly in the following sentences or paragraphs to improve coherence in writing.