1. But these early misgivings were not shared by everyone, and, in May 1968, one of Britain´s most eminent cardiac surgeons, Donald Ross, decided to perform the operation on 45-year-old Frederick West.
    但是，并不是所有人都怀有这种疑问。1968年5月，作为英国最著名的心脏外科医生之一的唐纳德·威斯决定给四十五岁的弗雷德里克·韦斯特进行心脏移植手术。

2. Because females do not have this tendency (this brain division is known to be influenced by male sex chemicals), girls who perform well in mathematics are doing so because they are superior in their overall mental development.
    因为女性不具备这种趋势（人脑的这种分工已知是男性激素影响的结果），数学好的女孩是因为她们的整体智力发育很好。

3. It is extremely difficult to estimate the true value of the services which people perform for us.
    但要估算别人为我们为所提供的服务的价值却是极其困难的。

4. They always perform their duties faithfully.
    他们总是忠实地履行自己的职责。

5. Yes,I got a good surgeon to perform the operation.
    是的, 我找一位好的外科医师动那个手术.

6. Just as many excellent instructors may not be effective online facilitators, not all students have the necessary qualities to perform well online.
    具备上述素质的人能够成为优秀的网络学生。

7. It may not be fair, but many people forget the valuable services the officers perform.
    这不太公正，但很多人还是会忽略海关官员所作的宝贵贡献。