see through someone

(verb) to know that someone isn’t telling the truth

Example Sentence:

Teacher: Why are you late?
Student: I’m sorry teacher, I had an appointment.
Teacher: Why do you have a Starbucks cup in your hand?
Student: Um….
Teacher: I can see through you. Please be honest with me.

Sandra saw through her boyfriend and his lies when she found a text message in his phone from another girl.

Similar idioms:

1. bite the hand that feeds one
2. live from hand to mouth
3. keep in touch
4. hand-me-down
5. full of it
6. give someone a hand
7. full of shit
8. draw a blank
9. hand in something
10. tell on someone