�。ㄕ`）I shouldn't do that if I was you.

　�。ㄕ�）I shouldn't do that if I were you.（表示與現(xiàn)在事實相反的虛擬語氣不能用was，必須were.）

　　2.中文：要是我父親現(xiàn)在在這里，他會告訴我該做什么。

　�。ㄕ`）If my father were here now， he will tell me what to do.

　�。ㄕ�）If my father were here now， he would tell me what to do.（表示與現(xiàn)在事實相反的虛擬語氣中，主句的助動詞只能用would，might等過去時。）

　　3.中文：要是我知道她的電話號碼，我就會給她打電話了。

　�。ㄕ`）If I knew her telephone number， I would have called her.

　　（正）If I had known her telephone number， I would have called her.（表示與過去事實相反的虛擬語氣中，條件從句的動詞要用過去完成時。）

　　4.中文：要是昨天沒下雨她也許會來。

　�。ㄕ`）If it had not rained yesterday， he might come.

　�。ㄕ�）If it had not rained yesterday， he might have come.（表示與過去事實相反的虛擬語氣中，主句的動詞要用助動詞的過去時might，could等＋HAVE＋過去分詞。）

　　5.中文：我不認為我會失敗，但要是我失敗了，我會再努力。

　　（誤）I don't think that I shall fail. But if I failed， I would try again.

　�。ㄕ�）I don't think that I shall fail. But if I should fail， I would try again.（表示與將來事實相反的虛擬語氣中，條件從句的動詞用should加原形動詞。）

　　6.中文：他要是帶了錢就會買它。

　�。ㄕ`）Did he bring some money with him， he would have bought it.

　�。ㄕ�）Had he brought some money with him， he would have bought it.（表示與過去事實相反的虛擬語氣中，條件從句的動詞要用過去完成時，若省略if，則用倒裝形式。）

　　7.中文：她要是個男人可能會當選總統(tǒng)。

　�。ㄕ`）Be she a man， she might be elected president.

　�。ㄕ�）Were she a man， she might be elected president.（表示與現(xiàn)在事實相反的虛擬語氣，不能用was，只能用were；若省略if，則將were放在句首。）

　　8.中文：我提議提高教師的薪資。

　　（誤）I suggested that the teachers' wages could be increased.

　�。ㄕ�）I suggested that the teachers' wages should be increased.（suggest當建議講時，后面的名詞從句的主要動詞要用should加原形動詞，should可以省略。）