2 . The trip is scheduled ________ on December 21 in New York City and continue on to Milan, Prague, Paris, Bangkok and New Delhi before ending in Toronto on January 8.

A．start

B．to start

C．starting

D．started

3 . The problems to be discussed at the meeting tomorrow are really hard ________.

A．to solve

B．solved

C．solving

D．to be solved

4 . We regret ________ you that the book you need is not available in this library.

A．having informed

B．informing

C．to inform

D．to have informed

5 . On social media sites, people tend ______ only positive updates that make them appear happy and friendly.

A．post

B．to post

C．posting

D．posted

6 . They told me ________ in touch and call them if I need help.

A．kept

B．keeping

C．to keep

D．keep

7 . Our teacher tells us that every means should be made use of _______the problem.

A．solve

B．solving

C．being solved

D．to solve

8 . With the problems ________, the newly elected president is having a hard time now.

A．solve

B．solved

C．solving

D．to solve

9 . We walked a long way to the library, only ________ that it was closed because of the Covid-19.

A．finding

B．found

C．to find

D．having found

10 . With many articles _______, he won’t have time to go shopping this morning.

A．to write

B．written

C．writing

D．wrote