So far, many dolphins worldwide have been captured and kept in small pools, performing for people, especially kids. These dolphins are fed on fish instead of having to _______them. Gradually, they start spending most of their time near the pool waiting for food rather than underwater. They get out of shape and can no longer _______for long distances, which affects their_______ greatly, and results in _______ consequences (后果).

Thus comes the question. “Should captive (被关起来的) dolphins be _______?” Jeff Foster, a dolphin expert, decided to help two captive dolphins, Tom and Misha, to reach their top physical_______. Every day, he trained the two dolphins to get used to their wild homes again. Twenty months later, Tom and Misha began to act like _______ dolphins and they were set free back into the sea.

_______Tom and Misha lived in captivity for 4 to 5 years, they were able to adapt to the wild. It was _______ what Foster had hoped for. His dreams for the dolphins had finally come true and he knew that the dolphins would ________ in the wild.

This program was successful, but there have been other failures. For example, another dolphin, Keiko, returned into the ocean in 2002, but________ a year later because of all the misery (痛苦) he ________ in the past. The sudden ________change did not suit him well.

If people want to avoid these accidents, we must go to great lengths and put ________to ensure it doesn’t happen ever again. In fact, with virtual reality technology picking up, there can still be great ways to ________ kids with sea animals without having to capture them.