parents say and do has a life-long effect on their children.
| A．That | B．Which | C．What | D．As |
All the photographs in this book, _______ stated otherwise, date from the 1950s.
| A．unless | B．until | C．once | D．if |
The limits of a person’s intelligence, generally speaking, are fixed at birth, but ________he reaches these limits will depend on his environment.
| A．where | B．whether | C．that | D．why |
The police still haven’t found the lost child, but they’re doing all they .
| A．can | B．may | C．must | D．should |
They are broadening the bridge to ________ the flow of traffic.
| A．put off | B．speed up | C．turn on | D．work out |
There are a small number of people involved, possibly ______twenty.
| A．as few as | B．as little as | C．as many as | D．as much as |