用作时间状语的关系副词when通常不能省略,但有一种特殊情况,即用于day,year,time等少数几个词后时可以省略(也可换成that).如:
Thatwastheyear(that)Ifirstwentabroad.
I'llneverforgettheday(that)wemet.
Thesecondtime(that)Isawhimwasin2000.
Idon'tknowtheexacttime(when/that)thesportsmeetingwilltakeplace.
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