Experiments of this kind ___in both the U．S and Europe well before the Second World War．
| A．had conducted | B．have conducted |
| C．have been conducted | D． had been conducted |
Margaret liked all her classes, but she liked sewing class _____.
| A．above all | B．in general | C．after all | D．in particular |
The problem had become _____ in his mind, and he could not decide what to do about it.
| A．simplified | B．exaggerated | C．matured | D．isolated |
The problem had become _____ in his mind, and he could not decide what to do about it.
| A．simplified | B．exaggerated | C．matured | D．isolated |
No one helped me . I did it all _____ myself
| A．for | B．by | C．from | D．to |
—Can I speak to Mr. Wang , please ?
— _______
| A．Who are you ? | B．I’m Wang . | C．Speaking | D．Are you john ? |