图钉

The teacher thumbtacked the notice on the bulletin board.

老师用图钉把通知摁在公告板上。

He puts thumbtacks on my stool.- You saw him do this?

他把图钉放在我的椅子上啦你都看到了？

"Yes, I know," said Mr. Kangaroo."I enjoy putting thumbtacks in chairs."

&是的，我知道，&：袋鼠先生说，&我喜欢把图钉放在椅子上。&

She dropped some thumbtacks on the floor.

她掉了一些图钉在地上。

It's great for those in-between prints that are too valuable to put thumbtacks through, but not valuable enough to have framed.

它非常适合于那些在中间，打印是太宝贵了把图钉通过，但有足够的有价值的框架。

Plus it's considerably cheaper than framing, and looks a lot better than thumbtacks.

加上它的价格低于大大框架，并期待很多比图钉。

I pressed the thumbtacks into the board with my thumb.

我有用大拇指将图钉钉在板上。

I pressed the thumbtacks into the board with my thumb.

我有用大拇指将图钉钉在板上。不适合

Kangaroo."I enjoy putting thumbtacks in chairs."

袋鼠先生说，&我喜欢把图钉放在椅子上。&

He put thumbtacks on the teacher's chair. He threw spitballs across the classroom. He set off firecrackers in the lavatory and spread glue on the doorknobs.

他在老师的椅子上放图钉，在教室里扔纸团，在厕所里放鞭炮，还在门把手上抹胶水。

Compared the voltage negative feedback wire-feeding speed regulation system supported by current positive feedback with the rotational speed negative feedback regulation system, the equivalent condition of the two systems is obtained. Then, a wire-feeding speed regulation circuit for the CO_2 welding machine is designed based on TL494 chip, which has the self-protective function under the condition of current overloading.

通过对电压负反馈配合电流正反馈的送丝调速系统与转速负反馈调速系统的比较，得出了这两种调速系统的等效条件，并采用电压负反馈配合电流正反馈技术，设计了一种以TL494为核心的具有过电流截止保护功能的CO_2焊机送丝调速电路。

Make a model to help you determine the optimal number of tollbooths to deploy in a barrier-toll plaza.

建立一个模型来确定在一个容易造成阻塞的收费区中应该设置的收费亭的最优数量。