What is the direct object in sentence David laughed and he lost his grip on lid?

The direct object in the sentence "David laughed and he lost his grip on the lid" is grip.

Here's why:

* "Lost" is the verb in the second part of the sentence.

* "Grip" is the thing that was lost.

* "On the lid" is a prepositional phrase that tells us *where* the grip was lost.

The sentence is structured like this:

* Subject: He

* Verb: Lost

* Direct Object: Grip

* Prepositional Phrase: On the lid