单选题 ______ the business letter, she made a copy and mailed it immediately.

单选题 If they ______ a few minutes earlier, they would have caught the train.

单选题 As a shareholder, how can I contact the company ______ stock I held.

单选题 More than 94 percent of our students are either employed ______ continuing their education six months after graduation.

单选题 ______ informal a meeting is, full preparation should be made to improve its effectiveness.

单选题 Only by using the latest technologies, ______ its goal for this year.

单选题 Parking can sometimes be a problem, so try to avoid peak periods ______ you travel by bus.

单选题 How we pack the products has a significant impact ______ the cost of logistics.