得 (补语)
RuleVerb + de + complement: evaluates how well or to what degree the action is done.
Curiosity
To rate how well an action is done, as in "he speaks well", where does the adjective attach?
Intuition
de is a bridge between the verb and its evaluation: "the action happened, and here is how well." It links the appraisal after the verb.
Visualization
Reorder the tempting [he][very well][speak] into Chinese [he][speak][de][very well].
Wrong order (rating first)
他subject很好complement说verb
得 complement (rating after verb)
他subject说verb得得 (links complement)很好complement
Essence
verb + de + complement. With an object, the verb repeats: ta shuo hanyu shuo de hen hao. The negative negates the complement: shuo de bu hao.
Examples
他说得很好。
He speaks very well.
她跑得很快。
She runs very fast.
我昨天睡得不好。
I did not sleep well yesterday.
Mini-quiz
Which expresses "she writes beautifully"?