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say / said
tell / told

To say v. Means to pronounce words or sounds, to express a thought, opinion, or suggestion, or to state a fact or instruction.

For example: "I often say the wrong thing."

Said v. is the past simple and past participle of to say. It can be used in direct speech:

For example: "I am sorry", said the criminal."

It can also be used in indirect (reported) speech (followed by that):

For example: "The criminal said that he was sorry."

Said adj. is used before the name of a person or thing you have already mentioned:

For example: "The said party denied the charges"

To tell v. means to say something to someone, often giving them information or instructions.

For example: "I often tell people how to practise their English."

Told v. is the past simple and past participle of to tell. It is normally used in reported speech, i.e. it is used to talk about what people say (followed by an object + that:):

For example: "I told him that I would be late."

When told has the meaning of "instruct", it can be followed by an object and an infinitive.

For example: He told me to leave.

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