They ___swim across the river.A can both B both can C are both D both are

问题描述:

They ___swim across the river.A can both B both can C are both D both are

A 因为若句中谓语动词包含情态动词或助动词时,both大多放在第一个情态动词或助动词之后.
can是情态动词,所以both放在它后面.