动词不定式肯定形式和否定形式
问题描述：
动词不定式肯定形式和否定形式
答
以下是动词不定式肯定形式和否定形式的例句：(1) 三个动词不定式肯定To work out this difficult problem in three days is impossible =It is impossible towork out this difficult problem in three daysTo lea...