作者：朱孔仁 贾利民
1. 【问】My leather tennis shoes are worn out. I need another pair. 第一句中的are worn out 是强调被动吗？第二句中的pair可以用one替换吗？
【答】wear out 意为"穿坏；用旧"，后面要接宾语。如果表示"某物被穿坏或用旧"则用be worn out。虽然该结构在形式上与被动语态一致，但它只强调状态，而不强调被动。
第二句中的pair 指的是a pair of leather tennis shoes, 故不能用one代替pair。
2.【问】Even though they're a little expensive, I'll take them. 句中even though的用法与even if一样吗？
【答】even though =even if, 用于引导让步状语从句，意为"尽管；即使；纵然"。它们引导让步状语从句时，若主句是一般将来时，从句通常用一般现在时代替一般将来时。
但二者又有区别：even though引导的从句的内容往往是事实；而even if引导的从句可能是假定性的。试比较：
Even though he knows it, he'll not let out the secret.（他知道这个秘密）
Even if he knows it, he'll not let out the secret.（不确定他是否知道这个秘密）
3．【问】The camera cost so much that I didn't buy one. 句中so可以换成such吗？
【答】不可以。so...that...与such...that...都可作"如此......以致于......"解，但二者所惯用的句型不同。so 通常用于以下几种句型：
1）so + adj. / adv. + that从句。如：
The book is so expensive that I can't afford it.
2）so + many / much / few / little + n. + that 从句。如：
He has so few friends that he is lonely.
3）so + adj. + a（an） + n. + that从句。如：
She is so clever a girl that we all like her.
而such 通常用于句型：such + (a/an) + adj. + n. + that 从句。如：
He is such a young boy that he can't go to school.