【C5】A．explainB．coverC．describeD．elaborate

Can you account for your absence from the class last Thursday？A．explainB．examineC．excuseD．

Recent pressure at work may account for his behavior.A.explainB.changE．C.influencE．D.embo

【C17】A．enormouslyB．efficientlyC．effectivelyD．elaborately

【C14】A．explainB．describeC．defineD．state

【C3】A．proficientB．efficientC．sufficientD．elaborate

【C15】A．explainB．illustrateC．analyzeD．compare