【C19】A．affirmativeB．optimisticC．confirmativeD．positive

【C19】A．advantageB．exceptionC．measureD．charge

【C19】A．plainB．earnestC．commonD．usual

【C19】A．tastelessB．tastyC．tastefulD．taste

【C20】A．systematicB．optimisticC．realisticD．statistic

【C18】A．positiveB．optimisticC．activeD．negative

The authors attitude in this passage is______.A．skepticalB．optimisticC．unclearD．objective