To the Teacher
This week’s lesson introduces the concept of bound morphemes, with struct being used as an example. The suffix –ion (-tion, -sion) is also introduced. Both elements are embedded in the article, “The Great Molasses Flood.”
To the Student
Morphemes are meaningful parts of words. Base morphemes are the main parts of the word. They form a base for the addition of prefixes and suffixes. Base morphemes can be free or bound. Free morphemes, such as help, act, and run, are words and can stand alone. Bound morphemes, such as struct, cannot stand alone. They need to have other morphemes attached to them. The bound base morpheme struct means “to build or put together.” It becomes a word when prefixes or suffixes are added to it. Construct (con+ struct) means “to build.” The new owners decided to construct a new entrance to the old building. Destruct (De+struct)means to “wreck or destroy:” The rocket will self-destruct when it passes through the Earth’s atmosphere. Obstruct (ob+struct) means to “get in the way of:” The road was obstructed (ob+struct+ed) by a huge boulder that had rolled down the steep hill. A structure (struct+ure) is something, such as a home, school, or factory, that has been built: The homes and other structures were damaged by the high winds.
Suffix –ion (-tion, -sion)
The suffix –ion is often added to words containing struct. The suffix –ion means “the act of doing something” and is used to make a noun out of a verb. Construct becomes construction (con+struct+ion) and means the “act of building:” The carpenters arrived at the construction site early. Destruct become destruction (de+struct+ion) and means the “act of being destroyed:” The hurricane caused widespread destruction. Obstruct becomes obstruction (ob+struct+ion) and means “the act of obstructing or getting in the way:” Boulders and other obstructions had to be removed before the road could be used. Reconstruct becomes reconstruction (re+con+struct+ion) and means “the act of rebuilding:” The reconstruction of the old building took months.
The Great Molasses Flood
Read about the destruction that was caused by the explosion of a tank of molasses. Then answer the questions that follow.
Molasses is a sticky, sweet liquid. In fact, in the olden days it was used to make candy. You wouldn’t think it would cause any harm. But a flood of molasses once caused the destruction of a whole neighborhood. Years ago, in the North End of Boson, there was a giant tank of molasses. The tank was 50 feet high and 240 feet around. It had just been filled and held more than two million gallons of thick, sticky molasses. The tank had been constructed in a hurry. It had not been fully tested to check for leaks or weak spots. It was winter when the tank was filled, but in January of 1919, the weather turned warm. This heated the molasses inside the tank and caused the thick liquid to expand. The tank’s structure was weak. The expansion was too much for it. Suddenly the tank blew apart. A 25-foot high wave of molasses poured out of the tank and left a path of destruction. It smashed everything in its path. It ripped the local firehouse off its foundations and carried it away. A truck was lifted up off the street and thrown into the Charles River.
Police, firefighters, and other emergency workers rushed to the North End to help save as many lives as they could. They had to get around smashed houses, fallen factories, and other damaged structures and broken furniture that had been shoved into the streets. But the biggest obstruction was the sticky pools of goo that they had to walk through. In some places, the molasses was waist high. Sadly, nineteen adults and two children lost their lives, and 150 people were injured. In the days that followed, molasses was tracked throughout the city by rescue workers and sightseers who had come to see the results of the molasses flood. Boston became a sticky city. In the North End, the smell of molasses lasted for years.
1. The flood of molasses caused the destruction of ________
a) most of the city b) a whole neighborhood c) the whole city.
2. The tank exploded because ______.
a) it was too high
b) its structure was weak
c) it had been damaged by storms
3. The biggest obstruction for emergency workers was ________.
a) pools of molasses b) furniture in the streets c) broken-down trucks
4. Altogether some ____ people lost their lives.
a) 15 b) 19 c) 21
More Info
If you want to find out more about the Great Molasses flood, check out these books:
Redding, A. C. (2025) The danger files: Real-life disasters. Candlewick Press.
Tarshis, L. (2025) I survived the great molasses flood, 1919. New York: Scholastic.
Finding Hidden Words
Words that seem difficult sometimes have easy words hidden inside of them. Sometimes the suffix –ion is spelled –sion as in pretension. Pretension seems to be a hard word, but if you look inside, you see preten. If you add a d to preten, you get the easy word pretend. When –sion is added to pretend, the d is dropped because otherwise the word would be hard to say. See if you can find the easy words in the following, Try unsuffixing the words. Take off the suffix –sion and add d or de.
Example: inclusion include
- division ______________
- explosion ______________
- decision ______________
- 4.conclusion ______________
- invasion ______________
Words Ending in t
In some words, the letter t is added after the suffix is removed from words ending in the suffix –sion. For instance, if you take away the suffix and the extra s from omission, you have omi. Add a t and you have the word omit. See if you can find the easy words in the following. Try unsuffixing the words. Take off the suffix and the extra s and add t.
- permission ______________
- submission ______________
- admission ______________
Answers
The Great Molasses Flood
- b 2) b 3) a 4) c
Hidden Words
1) divide 2) explode 3) decide 4) conclude 5) invade
Words Ending in t
1) permit 2) submit 3) admit
©Thomas Gunning, Ed. D.
Monday Morpheme Lessons
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