The new teller could not ______ how to use her calculator until the boss explained.A：amount toB：figure outC：add up toD：consult from

Dear Li Ming,
I heard that you had been admitted to a university.First,congratulations.I can well imagine how proud of your parents are now,since they have been anxiously hope to witness your success.And then,I would like to give you some suggestions about your preparations for university life.To begin with,you should set up your own goals about what you want to learn at the university and what you want to be after four years of learning.Then,based on your goals,you'd better start reading some books about your major and be familiar with your major.It helps you enter into a better condition early.Last but not the least,you should get used to an independent living soon.You have to cultivate a habit of independent living style.The earlier you rely on yourself,the quicker you can get a selfmotivated university life.That's all my suggestions.Hope you have a worthy summer holiday and enjoy yourself.

考查情态动词的用法。句意为：“我本应该去那里，但我没时间。”should have done表示“过去本应做的事而实际上并没有做”，常含有责备、遗憾的语气。

Dear Mr.Zhang,
We would like to invite you to visit our factory from November 15 to November 20 and give you an overview of our facilities and production methods.This would also be an opportunity for you to visit our Head Office in Los Angeles to meet our design team and Marketing and Sales Directors to discuss areas ofcommon interest.All the expenses will be assumed by us,for you are our guest.We can also put a company car and a driver at your disposal during your stay here.I do hope your schedule will allow you to accept our invitation.I look forward to meeting you here.
Yours sincerely,
Li Ming