人像摄影应充分运用调配角度、距离、空间的作用，才能取的良好的（）
A、视觉效果
B、透视效果
C、深度效果
D、距离效果
参考答案：B
梅毒引起的心血管病变主要见于（）
A.主动脉
B.冠状动脉
C.肾动脉
D.颈总动脉
E.肺动脉
For many years, people （） electric cars. However, making them has been more difficult that predicted.
A. had dreamed of
B. have dreamed of
C. dreamed of
D. dream of
