Why pleasant smells do not reduce pain i
题型:选择题
问题:
Why pleasant smells do not reduce pain in man is a question still _______ by scientists.
A.answered
B.being answered
C.to be answered
D.that answered
Why pleasant smells do not reduce pain in man is a question still _______ by scientists.
A.answered
B.being answered
C.to be answered
D.that answered