牵引梁的英文：
draft sill

draft是什么意思：
n. 草稿；草图；汇票；征兵，征集；通风装置；拉曳，牵引
v. 起草，设计；征（兵）；征集

They drafted him to serve as their delegate.
他们选派他作他们的代表。

DFL (Draft Full Load)
满载吃水装载量

They were unwilling to register for the draft.
他们不愿意登记入伍。

The boat has a shallow draft.
这条船吃水浅。

They were all a part of the drafting.
他们都参与了公约的起草过程。

sill是什么意思：
n. 基石;基木;门槛;窗台

Blown soil mounded on the window sill.
吹散的尘土堆积在窗台上。

There are no shortcuts to any place worth going. ——Beverly Sills
到任何值得去的地方都无捷径。

The sun in the west was a drop of burning gold that slid nearer and nearer the sill of the world.
西下的夕阳就象一滴燃烧着的金子，一点点滑向海平线。

A projection on a cornice or sill that protects the area below from rainwater.
滴水槽飞檐或窗台上的突出部分，用于防止其下方受水淋湿

She sit with one elbow resting on the sill of the open window.
她坐在那儿，一只胳膊肘搁在开着窗的窗台上。