4．
阅读下面材料，在空白处填入适当的内容(1个单词)或括号内单词的正确形式。
Alexandra Horowitz，a psychology professor and major researcher at the Horowitz Dog Cognition Lab at Columbia University，conducted one of the first ____(1)____ (study)on dog “guilt” in 2009．
She videotaped 14 dogs in a series of trials and observed ____(2)____ they reacted when their owners left the room after __(3)___
(instruct)them not to eat a treat．While the owner was gone，Horowitz gave some of the dogs the forbidden treat before ____(4)____ (ask)the owners back in．
In some cases the owners ____(5)____ (tell)that their dog had eaten the treat，but in ____(6)____ (other)，they were told their dog had behaved．However，Horowitz wasn't always honest with them．
Horowitz found that the dogs' guilty looks had almost nothing to do ____(7)____ whether they'd eaten the treat or not．In fact．dogs that hadn't eaten it but were scolded by misinformed owners
tended ____(8)____ (show)the most elements of the “guilty look”．
Horowitz says this shows that the dogs' body language is actually ____(9)____ response to their owner's behavior—not an experience of shame for a misdeed．
The guilty look would be ____(10)____ (well) called the “obedient look” as in “Don't punish me for whatever it is you think I did，”Horowitz wrote in The Washington Post．