在美国英语中,如果强调时间状语,that 可以用 when 替换。如:
It was after two o'clock in the morning when the surgeon arrived at the hospital. 在早上两点后,外科医生才到那家医院。(摘自《薄冰英语惯用法词典》P.435)
It was yesterday that [or when] I met him. 我是昨天见到他的。 (摘自《英汉多功能词典》新编升级版 p.899)