Don’t turn off the computer before closing all programs，________you could have problems.
| A．or | B．and |
| C．but | D．so |
I’m so ______ to all those volunteers because they helped my terrible day end happily.
| A．special | B．superior |
| C．grateful | D．attractive |
A ship in harbor is safe, but that’s not ______ ships are built for.
| A．what | B．whom | C．why | D．when |
Just as I got to the school gate, I realised I ______ my bank in the cafe.
| A．have left | B．had left |
| C．would leave | D．was leaving |
Only when Lily walked into the office ______ that she had left the contract at home.
| A．she realized | B．has she realized |
| C．she has realized | D．did she realize |
The quality of education in this small school is better than ______ in some larger schools.
| A．that | B．one |
| C．it | D．this |