— Not yet. It is too difficult for us.
A：development
B：difficulty
C：interest
His methods are regarded as the of working by his leaders and workmates.
下列句子中，没有语病的一句是（ ）
用计算器验证，下列不等式中成立的是（ ）
合作小组讨论“生命基本特征”时，出现下面4种说法，其中正确的是（ ）
