7. Marked Themes๏ƒ

Marked Themes play an important organising role in scientific and technical explanations. They help guide the reader through cause-and-effect reasoning and make the text easier to follow.

7.1. 1. Foregrounding the Cause or Condition๏ƒ

Marked Themes allow the writer to place the cause, condition, or context at the front of the clause. This helps readers understand the triggering situation before encountering the main clause.

Examples

When a bending force is applied, the chalk breaks.
When a metal is heated, it expands.
If the concentration of reactants increases, the rate of reaction increases.

7.2. 2. Highlighting Important Circumstances๏ƒ

Scientific explanations frequently depend on circumstances such as when, why, under what conditions, or in what manner a process occurs. Placing these circumstances in Theme position (first in the sentence) highlights their importance and clarifies the conditions under which the phenomenon happens.

Examples

Under high pressure, the gas compresses.
At low temperatures, reaction rates decrease.
In the presence of a catalyst, the reaction proceeds more quickly.

7.3. 3. Organising Logical Relations Clearly๏ƒ

Explanations rely on signalling relationships such as cause, effect, sequence, and contrast. Marked Themes often use text connectives (e.g. As a result, Therefore, Consequently) to make these relations explicit. These guide the reader through the chain of reasoning.

Examples

As a result, the particles collide more frequently.
Therefore, the pressure inside the container increases.
Consequently, more product is formed in a shorter time.