If it were not for ……
結構︰if it were not for+名詞/子句，主詞+would/should 等+原形動詞…
說明︰此句型意為“若非(有)…”。此類句構專門用於表示與現在事實相反的。亦可用“but for+”或“without+”代替。were 可以提前，省略 if，如例句 it were not for his presence，I would punish you.要不是他在場，我會處罰你的.。
But for your advice,I should have failed.要不是你的忠告，我會失敗的。
But for music (=Were it not for music),life would be dull.要不是音樂，人生會很無聊。
If it were not for oxygen and nitrogen in the air,no man could live on the earth.大氣中如果沒有氧和氮，人就無法生存於地球了。
Without air,all living things would die.若非空氣，所有的生物都會死亡。
Without newspaper,we would get behind the times.要不是報紙，我們都趕不上時代了。
I should be lonely,were it not for the birds and the flowers.我會寂寞，若非有鳥也有花。
Were it not for his help,I could not finish the work.若非有他的幫助，我就不能完成這件工作。
Were it not for science,we could not live a comfortable live.若非科學，我們無法過著舒適的生活。
If it had not been for ……
結構︰if it had not been for+名詞/子句，主詞+would/should 等+原形動詞…
說明︰此句型意為“若非(有)…”。此類句構專門用於表示與過去事實相反的。If it had not been for his help，I should have failed.如果沒有他的幫忙，我應該已經失敗。
Had it not been for your timely help,our company would have been on the verge of bankruptcy.若非你及時伸出援助之手，本公司將會瀕臨破產的邊緣。
If it had not been for these experiments,the improvement of the machine would have been impossible.要不是這些實驗，這部機器也許就不可能改良了。
Had it not been for the kind guide,I might have got lost in the mountains.要不是這位好心的嚮導，我可能就在山中迷路了。
If it had not been that he was here,I would have punished you.要不是他在場，我當時就會處罰你。
