Sometimes the predicate of a sentence will contain an object.
Sentence objects are of two kinds: direct and indirect.
A direct object receives the action of the verb. For example, if the verb describes an action that affects something else, it will usually be followed by a direct object:
The batter hit the ball.
Here the action is hit and the receiver of the action is ball. Ball is the direct object of the verb hit.
An indirect object also receives the action of the verb, but not directly. For example:
My mother baked me a cake for my birthday.
This sentence contains two objects:
My mother baked me a cake for my birthday. (direct object of baked)
My mother baked me a cake for my birthday. (indirect object of baked)
When a predicate contains two objects, the indirect object will always come immediately after the verb. Although it does not appear in the sentence, the word to or for is understood. For example:
My mother baked me a cake. (indirect object)
My mother baked [for] me a cake.The boy wrote his father a letter. (indirect object)
The boy wrote [to] his father a letter.
First, learn to identify direct objects. Then turn your attention to indirect objects.