Related Clues:

• Do arithmetic
• Put into the mix
• Put in with the rest
• Say more
• Put 2 and 2 together
• Lengthen (with "to")
• Ancient pyramid builders
• Word found on a dipstick
• Also say
• Cookbook verb
• Toss in
• Toss into the mix
• Verb used in recipes
• Gibe, with 'up'
• Keep talking