It is required that in no case ________ our password.
On April 12, 1961,_____27—year—old Yuri Gagarin(尤里.加加林)became the first human to go into_____ space.
_____ tins of dog food can we buy _____ the money? [ ]
We are sure that our football players will do________ best.
That’s Tom’s book, please_____it to him.