Lucien Tesnière was a French linguist who studied how words work together in sentences. His theory is called "dependency grammar" and it's like a map that shows how words are related to one another.
Imagine you are playing with blocks and building a tower. Each block is a word in a sentence. They all have to fit together in the right way to make sense.
Tesnière noticed that words don't just exist by themselves. They always connect to other words in a sentence. For example, the word "dog" might connect to "the" to make "the dog." And "the dog" might connect to "chase" to make "the dog chase."
Dependency grammar is a way to show these connections. It does this by drawing lines between the words in a sentence to show how they all connect.
By understanding how words connect to each other, we can better understand how sentences work and how to communicate effectively. Tesnière's work in developing dependency grammar has been really helpful for linguists and language learners alike.