人员在使用安全带时，必须系挂在作业上部的牢靠处。（）

人患曼氏裂头蚴病是由于误食了含活的裂头蚴的______，________，______，_______的肉而引起。

. James said that he'd like to work with some of the leading directors, first ______, and then hopefully ______ his own film.

A．learning; do

B．learning; to do

C．to learn; doing

D．to learn; to do

You’d better not always look up the new words ____________ the dictionary while reading. Sometimes we need to guess.

A．in

B．on

C．at

D．from

写合并是提高写缓冲利用率的技术。

煤堆上采样，采样点如何分布？深度应为多少？