11、Recognizing who the customer was, the manager was most apologetic and reprimanded the assistant severely.
recognizing：由于经理认出这个顾客是谁了，便竭力陪礼道歉......。这句话用现在分词短语作原因状语
most=very much

12、When Dickie was given the watch, he presented the assistant with the cloth bag.
hand sb sth /hand sth to sb：把...递给...
present sb with sth / present sth to sb ：把...交给...人(比较正式 )

13、He insisted on the assistant's counting the money before he left -- 30,000 pennies in all!
insist on doing/insist that + should do：坚决要求
Ex:
He insisted that the shop assistant should count the money before he left.

14、It took him four years to stage this elaborate joke simply to prove that critics do not always know what they are talking about.
simply to prove=only to prove
don't always know what they are taking about= don't always talk sense= always talk nonsense
Ex:
talk nonsense：胡说八道
talk sense：说正经话新概念英语免费下载