Review: Topic Sentences, Answer 4.3

Oops!

Question:

In Montréal, a flashing red traffic light instructs drivers to careen even more wildly through intersections heavily populated with pedestrians and oncoming vehicles. In startling contrast, an amber light in Calgary warns drivers to screech to a halt on the off chance that there might be a pedestrian within 500 metres who might consider crossing at some unspecified time within the current day. In my home town in New Brunswick, finally, traffic lights (along with painted lines and posted speed limits) do not apply to tractors, all-terrain vehicles or pickup trucks, which together account for most vehicles on the road. In fact, were any observant alien dropped from a space vessel at an unspecified intersection anywhere in this vast land, it could almost certainly orient hitself according to the surrounding traffic patterns.

Answer:

The answer people in Montréal drive faster than people in Alberta, and Maritimers generally don’t pay any attention to traffic signals at all is not correct.

Explanation:

The topic sentence should highlight the interpretative nature of driving habits and their regional variations. It is not enough simply to list all of the arguments in the paragraph (people in Montréal drive faster . . .), or to pick only one point to highlight (people in Calgary are careful of pedestrians). Since the paragraph stresses the differences among drivers in different parts of the country, it would be wrong to simply state in the topic sentence that Canadians do not follow traffic signals properly.