Add up something or Add something up phrasal verb
The conjugation of the main verb “Add” is “Add” “Added” “Added” “Adds” “Adding”
The phrasal verb “Add up (something) or Add (something) up” is used to mean “To calculate the total of two or more numbers”
Example: 1. Add all those figures up and it would amount $10,000.
Example: 2. The expenses adds up to more than 30 thousand.
Add up (This usage is never used in continuous tenses) (This usage is slightly informal)
The phrasal verb Add up is used to mean
1. to increase and become a large number or amount
Example: 1. If you save a few bucks every week, it will quickly add up to a large sum in a year.
2. to be a reasonable or likely explanation for something (This usage is often used in negative contexts.
Example: 2. She says she doesn’t like them and yet goes to places with them, Her behavior just doesn’t add up.