Examples of Topic Sentences

Here is an example of a paragraph with a clear topic sentence:

Topic sentence The topic sentence outlines what the paragraph will discuss. The body of the paragraph further explains and expands upon the point made in the topic sentence.

This design involves a redesign of the spindle mechanism of the outdoor tap. This involves replacing the turning action of the conventional tap with a new system where a lever provides the mechanical movement. Pulling the lever upwards engages a push-rod connected to the normal washer that forces the washer down towards the seat, preventing water flow. When the handle is released, a downward action on the lever opens the tap valve as the push-rod raises the washer, allowing water flow. The design incorporates a ratchet locking system, similar to that used in an automobile hand-brake, which allows the lever to be locked in a number of positions, provided by graduations in the ratchet. This allows the user to turn the tap on or off and set the flow rate, as per a conventional tap.

Here is another example of a paragraph with a clear topic sentence, yet in this example the topic sentence lies at the end of the paragraph.

Topic sentence Despite its position at the end of the paragraph, the topic sentence still provides an outline of the point/s the paragraph is focussed upon.

The passive voice is used in this paragraph to focus explicitly on what happened to the bacterial colonies rather than on who or what inhibited them. Nominalisation and large nominal groups are also used as devices to consolidate information about the actions/processes involved inside noun groups which can be then placed in the most focussed position in the sentence, i.e. sentence subject or sentence initial position. Together, the use of the passive voice, nominalisation and large nominal groups (along with the jargon of the discipline) play a major role in achieving the distinctive style or language of Biology.