http://chanyi.new21.net/zbxe/65003
 28. 가정법 과거
Point
현재 또는 장래에 있어서 실현 불가능(또는 실현 곤란)한 바람이나 현재의 사실에 반대되는 가정을 나타낸다.

형태
①      If 주어 + were                                       주어 + should/would
          동사과거형                                         could/might      + 동사원형
          조동사 과거형 + 동사원형~

② without / but for + 명사, ~
만약 ~라면, ~일텐데

Practice
․ If he were in your place, he [won't/wouldn't] do that.

․ Clearly, our lives would be better if we [act/acted] based on our careful consideration instead reacting to the feelings of the moment.

․ If today's top rock singer released his or her next piece on the Internet, it [will/would] be like playing in a theater  with 20 million seats.