What does “throw a spanner in the works” mean?

Do you know what “throw a spanner in the works” means?
 
Click on the correct meaning below:
 
[owad date="2011-11-14"]
 

ACTIVITY:

Use “throw a spanner in the works” in a sentence.

1. Put your sentence in the comments.
2. Read sentences written by others.

John will read all sentences and give you feedback!

 

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