Potential subjects should be informed of the research and _ an opportunity to decide if they want to participate.
No sooner had I got home _____ it began to rain.
They entail much lower transaction costs, faster communication and transaction speeds and _______ networking opportunities.
They had never travelled _______.
This year they had produced _________ grain __________ they did last year.
______ their return they discovered that their house had been burgled（入室盗窃）.
No sooner had I got home _____ it began to rain.
At no time in the history of mankind ________ greater opportunities for following careers they have now.
Many years had ____ before they returned to their original urban areas.
The police could not prove he had been involved in the crime, so they had to ________ him.
The new mechanism is not so effective as they had expected, for months passed and there has been no big improvement in management efficiency.
Once they had fame, fortune, secure futures; ______ is utter poverty.
根据听到的内容作答____. A) They were inefficient. B) They had wooden frames. C) They were spacious and airy. D) They didtr't provide enough light.
When they had finished playing， the children were made to__________all the toys they had taken out．
No sooner had I______than the play began.
When they arrived at the airport, they had ______.
They saw a new movie at the theatre, ________ they had dinner at a Chinese restaurant.
They are ______ in name, but they no longer teach students.
But balloons and the cigar-shaped airship, which was invented slightly later, did not solve the problem of flying because they had no means of power or control.
The weatherBeing unfavorable，they had to__________the sports meet,
Once they had fame, fortune, secure futures; ________ is utter poverty.
It’s a__into the adolescence they never really had（）
We walked slowly down the trail with great trepidation. No one who had gone this way had ever been heard from again. Had they simply found a better place to settle on this dark planet？ We doubted that
She had no____for jokes of any kind.（tolerant)
