A country produces only pencils and erasers. Pencil production is allocatively efficient if the marginal ________ of a pencil equals the marginal ________ of ________. A: cost; benefit; an eraser B: cost; cost; an eraser C: benefit; benefit; an eraser D: benefit; cost; a pencil

There’s ____ eraser on ____ desk. A: an ; the B: the ; a C: the ; the

There________ an eraser in the pencil box. A: is B: are

Weshouldtakepaper,__pencil,__eraser,__andknife.__此句话的语调顺序应为

The teacher accidentally hit the boy's hand with an eraser and was ___________ known as “Dead-Eye Bean”.

We should take paper, __ pencil, __ eraser, __ and knife. __ 此句话的语调顺序应为

The idea that the United States is a melting pot implies that racial differences are to be________(eraser) and that immigrants should give up their own cultural traditions.

使用什么位图工具可以对位图图像填充颜色？（） A: PaintBucket B: Pen C: Eraser D: Gradient

以下哪个单词的S不发音？ 未知类型：{'label': 'questionDesc', 'content': '请选择正确答案。', 'isMemberControl': 0, 'type': 181} A: Island B: Eraser

（）are the words in American English. A: Rooster, eraser, color, truck , mail B: Vacation, iii, travelled, licence, center C: Mail, traveled, sick, color, license D: Sick, truck, color, rooster, post