Why did the project come to a stop half way?
--- It was in part ______________ financial difficulties.
| A．away from | B．thanks to | C．owe to | D．due to |
They put forward a lot of plans at the meeting, none of _______ carried out in their work.
| A．which | B．them | C．what | D．that |
He had a lot of friends, only a few of ______ invited to his wedding.
| A．whom | B．them | C．which | D．who |
I met the fruit-pickers, several of _______ were still university students.
| A．that | B．who | C．them | D．whom |
Her sons, both of ______ work abroad, will come back home this summer.
| A．that | B．who | C．them | D．whom |
George, with _______ I played tennis on Sundays, was a warm-hearted person.
| A．that | B．him | C．them | D．whom |