The most important rule to writing effectively is to not repeat yourself. Each of these three rules focuses on avoiding repetition in English.
RULE 1: DON'T REPEAT THE SAME WORD
One of the most important rules in writing English is to avoid repetition. In other words, don't use the same words over and over again. Use synonyms, phrases with a similar meaning, and so on to 'spice up' your writing stile.
RULE 2: DON'T REPEAT THE SAME SENTENCE STYLE
In a similar way, using the same sentence structure by repeating the same structure over and over again is also considered bad style.It's important to know a variety of ways to make the same statement.
Here's a quick review of these forms:
句间副词短语，如as a result,however,otherwise等等。
RULE 3: VARY SEQUENCING AND LINKING LANGUAGE
Finally, when writing longer passages you'll be using linking wordsand sequencing to connect your ideas. As in word choice and sentence style, it's important to vary the linking language you use.
Instead of writing:
First, open the box. Next, take out the equipment. Next, insert the batteries. Next, turn the device on and begin work.
You could write:
First, open the box. Next, take out the equipment. After that, insert the batteries. Finally, turn the device on and begin work.