1正確.
對(duì)現(xiàn)在虛擬用過(guò)去式,對(duì)過(guò)去虛擬過(guò)去完成時(shí),對(duì)將來(lái)虛擬用過(guò)去將來(lái)時(shí),時(shí)態(tài)都倒退
因?yàn)橛衴esterday所以是對(duì)過(guò)去虛擬,用過(guò)去完成時(shí)??????????????????????? ????????????If??????????????????????????????????????????????????????????????????裩??If????ν??????ù??????????had+?????????????would/should/could/might+have+????????磺If he had know your address yesterday,he would have telephoned you.If you had come a little earlier,you could have met him. ????????????????????????????裩??If????ν??????????????(be?????were)????????would/should/could/might+??????Ρ??????????????? I ?????were????was???磺If I were you,I should do that. ???????????????????????????С?????????裩??If????ν?????????????????were to/should+??????Σ???????would/should/could/might+??????Ρ??磺If it should rain the crops would be saved.If it were to snow tomorrow,they wouldn??t go for an outing. ???????а???