英文問題 - 考試

各位大哥大姐，小弟近日閱讀英文短文後有以下問題，

請高人指點兩招，感謝。

1、 My power would fall, were I not to support it by new achievements.

請問這句的were是幹麻的?他的用法是?

2、 A good book is often the best urn of a life enshrining the best that life
could think out; for the world of a man's life is, for the most part, but
the world of his thoughts.

最後面兩句該如何翻譯以及它的用法是?

3、 Useful knowledge is the knowledge which is of benefit to ourselves and to
others, and that is the most important which is the most useful.

最後一句該如何翻譯以及它的用法是?

4、 It is important that in trying to learn to write well you learn to read
well.

that引導的句子該如何翻譯以及它的用法是?

再次感謝。

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