◆ Practice o Match the phrase on the left with its definition on the right o I act up a. to support; to move back wards 2 add up b to fail to work properly 3 add up to c. to have a certain value to be equal to sth 4 back down d to find the sum to combine: to take together ◆5. back up e to withdraw charges claims to retreat Practice:  Match the phrase on the left with its definition on the right.  1. act up a. to support; to move  backwards  2. add up b. to fail to work properly  3. add up to c. to have a certain value; to  be equal to sth.  4. back down d. to find the sum; to  combine; to take together  5. back up e. to withdraw charges,  claims; to retreat