Reading Complex Texts: Grammar, Cohesive Ties, Sentence Structure and Background Knowledge

Remember from Grade 8

In Grade 8 you used cohesive ties (pronouns, transitions, synonyms), found the core of long sentences, and activated prior knowledge from History and Science before reading about the Rideau Canal.

Grade 9 texts in Science, Geography and English are denser. This lesson adds two grammar features that make texts hard, the passive voice and nominalization, and shows how to use word parts and your knowledge from other courses.

Hook: who did it?

Read this headline: Mistakes were made.

Who made the mistakes? The sentence doesn't say. That's the passive voice: it can hide the doer. Complex texts use this often, sometimes for good reasons (the doer is unknown or unimportant) and sometimes to avoid blame. A strong reader always asks: Who did what?

Before reading: what do I already know?

You're about to read about zebra mussels in the Great Lakes. Before you read, gather prior knowledge from several sources:

• Personal experience: maybe you've cut your foot on sharp little shells at a beach, or seen a boat-washing sign at a launch.
• Grade 7 Science (Interactions in the Environment): food chains and food webs, and how invasive species disrupt ecosystems.
• Grade 8 Science (Water Systems): the Great Lakes hold a huge share of the world's fresh surface water, and human activity affects water quality.
• Geography: ocean ships reach the Great Lakes through the St. Lawrence Seaway. In Grade 9 Geography you study how Canada's water and natural resources are used and managed.
• Media: news stories about other invaders, such as the emerald ash borer that has killed ash trees in Ontario.

Write one thing from each source. Then predict: How could a tiny mussel change a huge lake?

Small Shells, Big Changes (an informational text written for this website)

(1) Zebra mussels are small freshwater mussels, about the size of a fingernail, that are native to the region around the Black Sea and the Caspian Sea. (2) The introduction of zebra mussels, which were carried across the Atlantic in the ballast water of cargo ships during the 1980s, has been linked by researchers to dramatic changes in the food webs of the lower Great Lakes. (3) Ships take on water to stay stable at sea and release it when they reach port; any living things in that water are released with it.

(4) These filter feeders strain tiny algae and other particles out of the water. (5) A large colony can filter enormous amounts of water, and lakes where they have spread often become noticeably clearer. (6) This clarity might sound like good news. (7) However, the algae the mussels remove are food for zooplankton, the tiny animals at the base of many fish food chains. (8) Clearer water also lets sunlight reach deeper, so plants and algae grow on the lake bottom where they did not grow before.

(9) The invaders cause practical problems, too. (10) Their shells crust over water intake pipes at power plants and water treatment plants, and removing them is costly. (11) They also attach to native mussels, which can starve or suffocate beneath them. (12) As a result, today's rules require many ships to exchange or treat their ballast water before entering the Great Lakes, and boaters in Ontario are asked to clean, drain and dry their boats before moving to another lake.

Glossary: ballast water: water a ship carries to keep it balanced. filter feeder: an animal that feeds by straining food particles out of water. zooplankton: tiny animals that drift in water. native: naturally belonging to a place. invasive species: a living thing brought to a new place where it spreads and causes harm.

Grammar that makes texts dense

1. Passive voice. The introduction ... has been linked by researchers to... The subject (introduction) doesn't do the action; it receives it. Turn it active by asking who did it: Researchers have linked the introduction ... to...

2. Nominalization. The introduction of zebra mussels hides an action (someone introduced zebra mussels) inside a noun. This clarity hides the water became clear. Nominalizations let writers pack a whole event into one word, then talk about it. Unpack them by turning the noun back into a verb.

3. Embedded clauses. which were carried across the Atlantic in the ballast water of cargo ships during the 1980s sits in the middle of the core, splitting the subject from its verb. Mentally bracket it, read the core, then add it back.

Cohesive ties across a whole text

Notice how many different words this passage uses for the mussels: zebra mussels, These filter feeders, the mussels, The invaders, Their, They. Each one tells you something new: filter feeders tells you how they eat; invaders tells you the writer sees them as harmful.

Summary words are ties too: This clarity (sentence 6) sums up sentence 5. If you missed sentence 5, This clarity makes no sense.

Word parts and context for discipline-specific words

Many science and social-science words are built from Greek and Latin parts:

• in- (into) + vad (go): invasive = going into a place where it doesn't belong.
• aqua (water): aquatic, aquarium.
• bio (life) + -logy (study of): biology; biodiversity = variety of life.
• zoo (animal) + plankton (drifting): zooplankton = drifting animals.

When word parts aren't enough, use context (the sentence around the word) and the glossary. Sentence 7 explains zooplankton right after the word: the tiny animals at the base of many fish food chains. That's an appositive definition, a built-in explanation.