【正文】 is that + 句子 （ ...的原因是 ...） 例句： The reason why we have to grow trees is that they can provide us with fresh air./ The reason why we have to grow trees is that they can supply fresh air for us. 我們必須種樹的原因是它們能供應我們新鮮的空氣。 二十二、 Since + S + 過去式， S + 現在完成式。 十九、 It is conceivable that + 句子 （可想而知的） It is obvious that + 句子 （明顯的） It is apparent that + 句子 （顯然的） 例句： It is conceivable that knowledge plays an important role in our life. 可想而知，知識在我們的一生中扮演一個重要的角色。 四、 There is no denying that + S + V ...（不可否認的 ...） 例句： There is no denying that the qualities of our living have gone from bad to worse. 不可否認的，我們的生活品質已經每況愈下。 九、 So + 形容詞 + be + 主詞 + that + 句子 （如此 ...以致于 ...） 例句： So precious is time that we can’t afford to waste it. 時間是如此珍貴，我們經不起浪費它。 例句： Since he went to senior high sch