1．(2017•全国卷Ⅱ)Later, engineers 68. ________ (manage) to construct railways in a system of deep tunnels(隧道), which became known as the Tube.
【答案】managed 考查时态。分析句子结构可知，68空所在句的句中没有谓语动词，故空处应填谓语动词。因为engineers与manage之间为主动关系且从时间状语later和became known as ... 可知应用一般过去时，所以应填managed。
2．(2017•全国卷Ⅰ)Fast food ________ (be) full of fat and salt；by eating more fast food people will get more salt and fat than they need in their diet.
3．(2017•全国卷Ⅲ)My dad thinks I should take the offer now. But at the moment, school ________ (come) first.
【答案】comes 由时间状语at the moment可知，这里是指现在发生的事情，因此用一般现在时。