Guide to English grammar

between 1700 and 1830 This period covers...
Britain's towns  towns had...
houses... designed architects planned...
three... periods... houses The houses of these periods are...
The houses of these periods They can...
Brighton Brighton became...
We can simply repeat a word (Brighton). Or we can use a pronoun if it is clear what it refers to (The houses... They...). Or we can repeat an idea in different words (... between 1700 and 1830. This period...). Here both phrases refer to the same thing, the period of time. The subject architects is also known information because we can relate it to houses were very well designed.
A subject can be in contrast with something mentioned before.
The towns were expanding rapidly. The villages, on the other hand,...

2 A subject can have an adverbial in front of it.

Previously, towns had grown naturally.
Previously is linked to this period.

For more on adverbials in front position, • 49(1).

A practical guide to English grammar 46

3 When a sentence starts with something known, it is usually easier to understand. If the link is not clear at first, then the reader has to work harder to understand the meaning. In this example, the word order of the second sentence has been changed.

...in many towns, especially in London, Edinburgh, Bath, Cheltenham and Brighton. After 1784, when the Prince of Wales, later King George IV, went to Brighton regularly, and later when he built the Royal Pavilion,...
The second sentence is now more difficult to read because the link with the previous sentence (Brighton) does not come at the beginning.

48 The subject

1 The subject often makes a link with the previous sentence.
The man is in prison. He stole some jewellery/ jewelry.
There was a break-in. Some jewelry was stolen.
The girls did well. Celia got the first prize.
There were lots of prizes. The first prize went to Celia.
We can often express an idea in different ways, e.g. Celia got the prize./The prize went to Celia. It is best to choose a subject that relates to what went before.

2 The subject can express ideas such as time and place.

This has been an eventful year for us. September saw our move to new offices. (= We moved to new offices in September.)
The house was empty, but the garage contained some old chairs. (= There were some old chairs in the garage.)
They're building a new theme park. It will attract lots of visitors. (= Lots of people will visit it.)

3 Sometimes we can use an abstract noun to refer back to the idea in the previous sentence.

Someone threw a stone through the window. This incident upset everyone.
Lucy had finally made up her mind. The decision had not been easy.
Brian is an impossible person. His rudeness puts people off.
The people here have nothing. Their poverty is extreme.