The course normally attracts 20 students per year, _____ up to half are from abroad.
| A．of whom | B．for whom | C．in which | D．with whom |
As I was worried about the safety of my son in the heavy storm, my attention began to _______ off my work.
| A．wonder | B．wander | C．separate | D．divide |
_________in the IT company, David decided to say goodbye and start his own business.
| A．Having ignored | B．To be ignored | C．Ignored | D．Ignoring |
I think it’ll take at least another two months _______ the shopping center is completed.
| A．until | B．before | C．when | D．as |
A child who lives in an uninteresting environment will develop less intelligence than ______ who lives in a rich and changing environment.
| A．the one | B．one | C．those | D．that |
Ted ______ for two months in London last year to receive his yearly training.
| A．stayed | B．has stayed | C．had stayed | D．would stay |