Keep up good state of mind even if you _____ fail plenty of times.
| A．must | B．will | C．can | D．should |
Seeing the happy________of children playing in the park，I’m full of joy and confidence in the future of our country.
| A．sight | B．scene |
| C．view | D．sign |
After five hours’ drive，they reached________they thought was the place they had been dreaming of.
| A．where | B．what |
| C．which | D．that |
Professor Backman took up scientific research for decades，and this is________he devoted all his life to.
| A．which | B．what |
| C．where | D．how |
Sorry I’m so late，but you cannot imagine________great trouble I took to find your house.
| A．what | B．how |
| C．which | D．why |
Water，which seems so simple and common，is________makes life possible.
| A．what | B．that |
| C．which | D．how |