COLUMBUS, Ohio—The heart operation taking place in the pale-green operating room at the Ohio State University Medical Center was unusual. The patient, a 62-year-old man, was made to sleep, tied with blue drapes（消毒帷帘）and lying face up on a narrow table. But no one was touching him.

Instead, the operation was being performed by a robot, whose three metal arms went through pencil-sized holes in the man’s chest. At the ends of the robot’s arms were tiny metal fingers, with turning wrists, which held a tiny instrument, a light and a camera. The robot’s arms and fingers were controlled by Dr. Randall K. Wolf, sitting at a computer in a corner of the operating room about 20 feet away.

This sort of operation, heart surgeons say, is the start of what may be the biggest change in their profession since heart bypass surgery（心脏搭桥手术）began nearly 30 years ago. “The reason we make cuts is that we have big hands,” said Dr. Wolf, the director of the surgery at Ohio State. The robot’s dainty fingers, no longer than a nail on the small finger, at the end of the long sticks could work better.

Eventually, surgeons believe, most heart surgery will be done by robots whose arms are put in through pencil-sized holes punched in patients’ chests. Instead of directly staring into a patient’s body, surgeons will view magnified images of the operation on computer screens. In theory, the doctor would not have to be in the same room, or even the same country, as the patient.

1.In this passage, the underlined word “dainty” means ______.

2.According to the passage, the reason that most operations require large cuts is that ______.

3.The main idea of this passage is that heart surgery by robots ______.

4.Based on the information in this passage, all of the following conclusions are true EXCEPT ______.