You can't imagine that a top student          ______ have failed in the college entrance examination. 

He did not regret saying what he did but felt that he         it differently. 

—What does the sign over there read?—"No person_______ smoke or carry a lighted cigarette, cigar or pipe in this area．"

Wen Jiabao told the orphans in Wenchuan  Earthquake not to cry.His words ____not  have calmed them instantly,but his concern  about common people was obviously seen.

— Jenny looks hot and dry.— So______ you if you had a high fever.