The ship was assigned to beacon the shoals.

这船被指定用来标志浅滩。

The herrings usually live in large shoals.

青鱼通常生活在大的浅水区。

Shoals of tourists come here in the summer.

这里夏季常有大批游客。

But real shoals do not existto swim in circles.

不过真实的鱼群并不只是转圈游动。

But real shoals do not exist to swim in circles.

不过真实的鱼群并不只是转圈游动。