问题补充:
Professor Smith, along with his assistant, on the project day and night to meet the deadline.
A. work
B. working
C. is working
D. are working
答案:
A. work
B. working
(答案→)C. is working
D. are working
解析:考查主谓一致。along with连接两个并列主语时,谓语动词和前一个主语保持一致,句子主语是Professor Smith,所以谓语动词用单数形式,选C。