The companies are working together to create _________ they hope will be the best means of transport in the 21st century.
| A．which | B．that |
| C．what | D．who |
So far, several ships have been reported missing _______ the coast of Bermuda Island.
| A．off | B．along |
| C．on | D．around |
It used to be thought _____ the Earth was flat.
| A．as | B．when |
| C．since | D．that |
He made _____ known to his friends that he didn’t want to enter politics.
| A．that | B．it |
| C．himself | D．him |
Why shouldn’t I buy a new coat — I haven’t bought _____ for five years.
| A．it | B．that |
| C．one | D．which |
There he pointed to _____ looked like a stone and said that’s ______ you had to carry home.
| A．that, that | B．what, what |
| C．which, what | D．as, which |