(2013·高考安徽卷)David is ________ animal fur，so he won’t visit anyone who has cats or dogs in the house.

You’d better give up using that kind of medicine, because it may be______ to your stomach.

The twins are so much__________that it is difficult to tell one from the other.

 Scientific research shows that animals can show         emotions like human beings. They are sometimes lively, and sometimes bad-tempered.

 ________ other good students, in my opinion, Tom is _________ student.