单项选择题
Is there any possible ______ explanation for his bad health since he seems to have no obvious disease
单项选择题 She refused to ______ the door key to the landlady until she got back her deposit.
单项选择题 No longer are contributions to computer technology confined to any one country; ______ is this more true than in Europe.
单项选择题 This disease ______ itself in yellowness of the skin and eyes.
