Mark needs to learn Chinesehis company is opening a branch in Beijing.(·山东 26)A. unles

问题补充：

Mark needs to learn Chinesehis company is opening a branch in Beijing.

(·山东，26)

A. unless

B. until

C. although

D. since

答案：

A. unless

B. until

C. although

D. since

解析：D

解析考查状语从句——原因状语从句。根据题意，前后之间为因果关系，因为要开分公司，所以需要学习汉语。答案选D。