If somebody says something and you don't believe them, there are many ways of saying you don't believe. Here are ten of them.

You're having me on.
You're pulling my leg.
That's a bit of an exaggeration.
That's an outright lie.
That's a pack of lies.
That's a fishy story.
What you're saying is libellous.
A half-truth.
That's a fib.
That's stretching the truth a bit.

Explanations

• Phrases 1 and 2 suggest that the other speaker might be lying as a joke.
• Phrase 3 suggests that the other speaker has described something as larger or stronger than it really is.
• Phrase 3 is a strong accusation that the previous statement is totally untrue.
• Phrase 5 suggests that the other speaker has made a number of statements and that all of them are untrue.
• Phrase 6 suggests that you are suspicious of a statement but you are not sure that it is a lie.
• Phrase 7 says that the statement is untrue and could be punished in a law court.
• Phrase 10 is the most gentle of these phrases but often the speaker still thinks the previous statement was a complete lie.