Phrases like ‘This is’ are often used at the beginning of sentences. But what is ‘This’? Be nice to the reader: don’t make them guess what you mean.

Words like this, that, these, and those can cause trouble by making your writing less clear, especially when they’re used to start a sentence. Look at the following two sentences.

The algorithm must be implemented in an efficient way, although certain difficulties will be encountered. This will be discussed further in the final section of this paper.

What exactly will be discussed in the final section of this paper? Does the word This refer to the expected difficulties, or to the efficient way of implementation, or perhaps even to the algorithm itself? The writing isn’t clear, so the reader has to guess. And readers don’t like guessing! (Here’s a good argument that the goal of academic texts is to make to the reader interpret as little as possible.)

To make This more clear, all you have to do is repeat the noun that This refers to, and there is no longer any doubt about which concept(s) you are talking about.

The algorithm must be implemented in an efficient way, although certain difficulties will be encountered. This algorithm will be discussed further in the final section of this paper.

or

The algorithm must be implemented in an efficient way, although certain difficulties will be encountered. These difficulties will be discussed further in the final section of this paper.

You don’t have to repeat a noun verbatim, but you do have indicate which part of the sentence you are referring to.

The algorithm must be implemented in an efficient way, although certain difficulties will be encountered. This implementation strategy will be discussed in the final section of this paper.

If you want to refer to the whole first sentence instead of just one word from that sentence, that’s easy to do too; just say what you mean.

The algorithm must be implemented in an efficient way, although certain difficulties will be encountered. This entire process will be discussed in the final section of this paper.

And there you have it — a quick, easy way to make your writing more clear!