This is the 409th most frequent German word.
legte
"Legte" is the simple past tense of "legen," meaning "laid" or "put."
In this sentence, 'legte' is the simple past tense of 'legen', meaning 'to place'. It refers to physically placing an object.
Er legte das Buch auf den Tisch.
He placed the book on the table.
In this example, 'legte' refers to the action of the dog lying down, as part of the reflexive verb 'sich legen', which means 'to lie down'.
Der Hund legte sich unter den Baum.
The dog lay down under the tree.
Here, 'legte' is used metaphorically in the phrase 'großen Wert auf etwas legen', which translates literally as 'to place great value on something' and means to emphasize or value.