Say Someone and Tell to Someone - Grammatical Explanation

Question

My friend often makes grammatical mistakes by adding "to" when it's not appropriate (Tell to him, ask to him...) or removing "to" when it should be included (I said him - meaning I told him).

I searched the internet for a definition or grammatical name for verbs that should be followed by "to" and those who shouldn't. I only found explanations about transitive and intransitive verbs, and direct and indirect objects but they don't seem to be related to the issue at hand.

Is there a rule for this type of structures (when to use "to" between a verb and its object and when not)?

Answer 1

There are not general rules. There are various patterns, but you cannot generally predict which verbs fit into which patterns.

Say is a transitive verb where the object (the utterance) is normally obligatory:

I said it.

You must say the words.

but not

*He said.

(Because what is said can be quoted words, the direct object can precede, in a way that is not normal for other verbs:

He said "I'll do it". or "I'll do it", he said. )

Like many verbs, say can take a to phrase, specifying who the words are said to:

He said it to me.

Say "I'll do it" to her.

This is not an essential argument of say, and you cannot use the special "ditransitive" syntax, as you can for give:

I gave the cake to John = I gave John the cake.

I said the words to John. but not *I said John the words.

Tell has two different possible patterns.

One use is ditransitive, with a direct object for the message, and an indirect object for the person told:

She told a story to the children = She told the children a story.

(The same two patterns as give).

but it can also be used without the message, in which case it is transitive, with the person being the direct object:

She told him but not *She told to him.

In summary

Say must have an object (the words said, which can precede if they are directly quoted), and it may have a to phrase; if it does, the to is obligatory.

Tell may have one or two objects. If it has only one, the object is the person told, and to is not allowed. If tell has two objects, then the message is direct, and the person indirect. The indirect object needs to unless it precedes the direct object (same pattern as give).

Answer 2

Fortunately, the rules for these verbs are pretty simple. Your friend just has to learn the grammar structure of each of these reporting verbs, and there aren't many.

These grammar structures below (in [brackets]) don't include every correct way to use these verbs, but they include the most natural ways, and are always going to be correct.

[ "say" + something ] (direct speech, no indirect object)

She said, "Come with me".

[ "say" (+ "to" + someone) + "that" + clause ] (indirect speech)

She said (to Harry) that his shirt was inside-out.

[ "tell" + someone (something) ] (give information; indirect speech)

I told her that I wasn't interested.

[ "tell" + someone + "to" + infinitive ] (give instructions or an order)

They told me to improve my writing skills and apply again in three months.

[ "ask" (+ someone) (+ something) ] (ask for information; direct or indirect speech)

He asked Sally, "What's your last class on Tuesday?"
He asked Sally what her last class on Tuesday was.

[ "ask" + someone + "to" + infinitive ] (give instructions or an order)

I asked him to wash the floor.