在装配件上有若干个平面时，应选择较小的平面作为装配基准面。( )
参考答案：错
把1～9各数填在下面方框里，使等式成立。
□+□+□=15
Being afraid of falling behind the times, he has always been keeping himself ___ of the latest development of technology.
A. instructed B. intended C. informed D demanded
