The verbs say and tell have similar meanings. They both mean "to communicate verbally with someone". We often use them differently, though.
The simple way to think of say and tell is:
You say something.
You tell someone something.
You say something
I say – He/She/It says – We/They say
I will say – I am saying – I said – I have said
When we use ‘say’, we do not use an object (e.g. me/them/you) immediately after the verb. The verb ‘say’ is used when we quote people directly and also when we give instructions. For example:
Angela said she would be back soon.
Angela told me that she would be back soon.
What did he say to you?
He said that he has had a wonderful morning?
The weatherman said it would rain today.
I won’t say this again! – Will you please get ready for school now?
You tell someone something
I tell – She/He/It tells – They/We tell
I will tell – I am telling – I told – I have told
When we use ‘tell’, we also include the object (e.g. you/her/us) immediately after the verb. The verb ‘tell’ is used when we say something to someone, and is commonly used when giving an order or instruction. For example:
I said to my manager that I'm busy today.
I told my manager that I'm busy today.
What did you tell them?
I told them that they need to be more productive.
I told my son to brush his teeth.
The teacher told the class to do their homework.
The teacher said to the class to do their homework.
You forgot to tell me to bring my swimming suit!
I told her that I want to [get,have] a pet.
Sometimes ‘say’ and ‘tell’ can be used interchangeably to express the same meaning when information is being passed from one person to another. In this case, the construction would be: ‘tell’ + object or ‘say’ + ‘to’ + object. For example:
Laura told me that she would be late for work.
Laura said to me that she would be late for work.
Remy said that he was tired. (reported speech)
Remy told [his doctor,Jane] that he was tired.
Anthony says you have a new job. (reported speech)
Anthony tells me you have a new job.
Taras said: "I love you." (reported speech)
Taras told John that she loved him.
My colleagues told me that my presentation wasn't bad.
Personal object
We usually follow tell with a personal object (the person that we are speaking to). We usually use say without a personal object:
She told me that she loved Juan.
She told me that was dinner was ready.
She said that she loved Juan.
She said that dinner would be ready soon.
He told everybody that he had to leave.
I told everybody in the group that they need to work harder.
He said that he had to leave.
Say "to someone"
With say, we sometimes use "to someone":
He said to me that he was tired.
What did you say?
I said that I'm going to spend my vacation with my friends.
What did she tell her brother about the New Years party?
She said that the party was cancelled.
He told someone that he was tired.
Tara said to Ram that he had done very well.
Tara told someone that he had done very well.
Anthony said to her, "I hope you come soon."
"I'd like to sleep," she said to him quietly.
Direct speech
We can use say with direct speech. We use tell only with direct speech that is an instruction or information:
Amanda said, "Hello John. How are you?"
My wife asked, "Honey, when are you going to work?"
"That's great," she said.
He told her: "Open the door quietly."
She told me, "I have never been to England."
We can use say with direct questions, but we cannot use tell:
She [asked,said]: "Do you love me?"
The policeman [asked,said to] the prisoner, "Where were you at 8pm?"
Reported speech
We can use say and tell to talk about reported information:
She said that it was [windy,snowing,raining].
My boss said that we are over budget.
My son said that he needs a new phone.
She told me that she would call at 4pm.
He told me that we will leave the office early today.
We cannot use say or tell to talk about reported questions. We must use ask(or a similar verb):
She asked if I had ever been there.
My boss asked if I completed the report.
They asked what I wanted to eat.
They asked when will the party start.
She asked where he lived.
He asked if she wanted to go home.
Orders, advice
We use tell + object + infinitive for orders or advice:
What did you tell him?
I told him that he needs to improve his leadership skills.
She told him to sit down.
My wife told my son to clean up his room.
My doctor told me to exercise more.
They told me not to wait.
My dentist told me to brush my teeth more often.
Tell Nancy to take a holiday and forget him.
Phrases
Here are a few fixed phrases with tell. We cannot use say with these phrases:
tell (someone) a story
tell (someone) a lie
tell (someone) the truth
tell the future (= to know what the future will bring)
tell the time (= know how to read a clock)