A. on
Đáp án D
Đại từ quan hệ “which” thay thế cho “speed”, mà ta có “at speed” : với tốc độ.
Dịch: Trí thông minh là tốc độ mà ta có thể hiểu và phản ứng kịp với những tình huống mới.
Ann's encouraging words gave me _________ to undertake the demanding task once again.
The local people insisted that the road_________50 cm more so that, in case of flood, they still can travel on it.
He did not share his secrets with other people but he ________in her.
The girl __________ design had been chosen stepped to the platform to receive the award.
My boss's plane___________at 10:15 tomorrow morning, but I cannot pick him up.