问题
选择题
—Must we finish the work before six?
—No, you ______. You can do it tomorrow.[ ]
A. can't
B. needn't
C. mustn't
D. may not
答案
答案：B
搜题请搜索小程序“爱下问搜题”
—Must we finish the work before six?
—No, you ______. You can do it tomorrow.[ ]
A. can't
B. needn't
C. mustn't
D. may not
答案：B
2SO3(g) ΔH<0，某研究小组研究其他条件不变时，改变某一条件对上述反应的影响，下列分析正确的是（ ） 