To cotton on is to begin to understand or know something.
Often used with ‘to’.
Examples of use:
1. He has cottoned on to what we are planning for his birthday!
2. Do you think she will cotton on to the fact that they are going on holiday without her?
3. My students sometimes find it difficult to understand how to use phrasal verbs, but they always cotton on in the end.
||cotton on and cottons on|
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