(1)He didn’t have _____vacations last year. This year he has even____ vacations.
(2)There are very _______robots now, but I think there will be a lot _____in the future.
(3)Young workers usually make ______money than old ones. And they have to spend _________
time on the new work.
(4)The scientists tried _____ times, but they still don’t have any information about the UFO.
(5)If I spend __________ time on study, I am sure I will get better grades.
最好有详细的解说