Omission of To and FOR before indirect objects

 1. Indirect object can be placed first and rhe preposition to omitted.

I gave the book to Tom.

Or, I gave Tom the book.

We can use this construction before the following verbs: bring,  give,  hand, leave ( in a will), lend, offer, pass (hand), sell, send, pay, Play (an instrument / piece of music), promise,  show, sing, take, tell( narrate, inform)

2. Putting the indirect object first and Omitting for.

This construction is possible after: book, build, buy, cook, (bake, boil, fry), fetch, find, get, keep, knit, leave, make, order, Reserve) 

I'll get a drink for you = I'll get you a drink. 

I bought a book for James = I bought James a book.

B

1. The construction without preposition is preferred when the direct object is a phrase or a clause.

Tell her the whole story.

Show me what you have got in your mind.

2. 

a. The construction with preposition is preferred when the direct object is a phrase or a clause. 

I kept seats for everyone on our list/ for everyone who had paid.

I had to show my pass to the man at the door. 

b. When the indirect object is it or them, preposition can not be omitted. (Can not be expressed by a verb + noun + pronoun.)

I kept it for Mary. 

She Made them for Bill.

C

Promise, show, tell can be used with indirect objects only, without to.

promise us. Show him. Tell him.

Read, write can be used similarly,  but require to.

Read to me,  write to me.

Play,  sing can be used with to or for.

Play to us or Play for us. 

Sing to us or  sing for us