Question

4.  (2015 江苏连云港东海一模) I had waited for several weeks without        Sam so I emailed him again.

   A. hearing from       B. hearing of

   C. hearing about        D. hearing out

Answer 1

4.A句意;我已经等了好几周也没有收到萨姆的来信，所以我再次给他发送了电子邮件。

hear from Sb.收到某人的来信。