Great changes _________ in my hometown in the past 20 years.
| A．took the place | B．have taken place | C．were taken place | D．took place |
As he reached _____ front door, Jack saw _____ strange sight.
| A．the; 不填 | B．a; the | C．不填a | D．the; a |
_______ that he was in great danger, Eric walked deeper into the forest.
| A．Not realized | B．Not to realize | C．Not realizing | D．Not to have realized |
_____twice, the postman refused to deliver our letters unless we chained our dog.
| A．Being bitten | B．Bitten | C．Having bitten | D．To be bitten |
We are invited to a party______ in our club next Friday.
| A．to be held | B．held | C．being held | D．holding |
Tony was very unhappy for ______ to the party.
| A．having not been invited | B．not having invited |
| C．having not invited | D．not having been invited |