By making friends with native speakers, one can _____ a lot of their languages. [ ]

A. set up

B. pick up

C. bring up

D. take up

以下（）不是真空负压吸盘的特点。

A、结构简单

B、重量轻

C、表面吸附力分布均匀

D、可以吸取重的工件