Very little is known about Antarctic killer whales.我們對虎鯨的所知有限

know about:知道； 了解； 聽說過有關 ... 的情況

I'd love to know about the plan.

我想知道這個計劃。

I happened to know about him.

我正好了解一些他的情況。

assign用法:

1.在美國，assign指“指定（功課）”，而其名詞形式assignment則指“被指定的功課”，其后通常跟in

，如an assignment in accounting；

2.注意assign后可加賓語，加to，再加名詞或代詞。不過習慣上常不用to。

The authorities assigned him to an important task.

他分配到了一個很重要的任務。

The authorities assigned him an important task.
上級給他分配了一個很重要的任務。

Series producer Martha Holmes and cameraman David Baillie were on board節目制作人瑪莎霍姆斯和攝影師大衛貝利在飛機上

on board:在船（車或飛機）上

Many of the tourists on board had begun bargaining with the tradesman.

船上的很多旅客開始與商人討價還價了。

On this trip, some time on one of the helicopters is assigned to the Life team.這一趟行程中，他們將一架直升機指派給“生命脈動”團隊

be assigned to:歸屬于, 被指派

Jack was assigned to the assembly shop of the factory.

杰克被分配到廠里的裝配間工作。

All the students are assigned to suitable jobs.

所有的學生都分到了合適的工作。