单项选择题
If we（）more time and money, we could have visited many more places.
A．have B．had had C．have had D．could have
单项选择题 Generally, it takes courage for an aged person（）a new life in a strange country.
单项选择题 （）you choose to contact us, you can expect our efficient and helpful service.
单项选择题 People invest money in this company（）they believe it will make profits.
