飞机起飞前，乘务员的职责之一就是确保所有乘客都系好安全带．（ensure）．

Question

飞机起飞前，乘务员的职责之一就是确保所有乘客都系好安全带．（ensure）___．

Answer 1

Before the plane takes off，one of the flight attendants duties is to ensure that all the passengers have fastened their safety belts．这是描述的乘务员的基本职责，所以用一般现在时．本句可用before引导...