Use 'choke up' when emotions are overwhelming and speech is difficult. At the wedding, I choked up during my toast.
Pro Tip 2/3
Sensitive Topics
'Choke up' often relates to topics like loss or love that easily stir emotions. She choked up whenever she visited the memorial.
Pro Tip 3/3
Not Literally Choking
Don't confuse 'choking up' with physically choking; it's about feeling, not breathing. Reading his letter, I choked up but there was no danger of suffocation.