比（Prep.） "than" 
   In addition to the usage introduced in Dialogue1, Lesson7, sometimes, 比can be used with a quantity complement indicating an actual amount or extent.

           A+比+ADJ.(了)+quantity complement
Examples :
1. 我们的成本比他们的成本多一百元。
Our cost is one hundred dollars more than theirs.
2. 块新比平信块两天。
Express mail is two days faster than regular mail.

Substitutive drills: