16、世上没有什么比…更令我高兴。

　　Nothing in the world can delight me so much as …

　　例︰世上没有什么比到快餐店吃汉堡更令我高兴。

　　Nothing in the world can delight me so much as having hamburgers in fast-food restaurants.

　　17、… 是必要的 It is necessary that S （should）V

　　… 是重要的 It is important/essential that S （should）V

　　… 是适当的 It is proper that S （should）V

　　… 是紧急的 It is urgent that S （should）V

　　例︰我们当保持公共场所清洁是应当的。

　　It is proper that we （should） keep the public places clean.

　　18、每当我听到…，我就忍不住感到兴奋。Whenever I hear …，I cannot but feel excited.

　　每当我做…，我就忍不住感到悲伤。Whenever I do …，I cannot but feel sad.

　　每当我想到…，我就忍不住感到紧张。Whenever I think of …，I cannot but feel nervous.

　　每当我遭遇…，我就忍不住感到害怕。Whenever I meet with …，I cannot but feel frightened.

　　每当我看到… 我就忍不住感到惊讶。Whenever I see …，I cannot but feel surprised.

　　例︰每当我想到我家附近那一条清澈的小溪，我就忍不住感到悲伤。

　　Whenever I think of the clean brook near my home，I cannot but feel sad.

　　Every time I think of the clean brook near my home，I cannot help feeling sad.