若单项式﹣5xmy2与5ynx4的和为0,则m﹣n=( ).
2
拼读选词 根据句意和音标从每题A、B、C、D四个选项中,选出一个适当的单词。(5分)
小题1:I’d like ______ /sʌm / noodles for breakfast.
A.swim
B.some
C.come
D.sun小题2:He is too ______ /ʃɔ t/ to get the book on the shelf.
A.shy
B.shoes
C.short
D.sport小题3:My parents ______ / liv / in a new building in the village.
A.live
B.leave
C.life
D.left小题4:Li Min wants to _________/ im'pruv / her English.
A. important
B.improve
C.enough
D.encourage小题5:Eating more__________ /`veʤitəblz / and less meat is good for your health.
A. villager
B.visitors
C.volunteer
D. vegetables
与强碱性树脂相比,弱碱性OH型树脂具有()的特点。
A.交换性能好,易用碱再生
B.交换性能好,不易用碱再生
C.交换性能差,易用碱再生
D.交换性能差,不易用碱再生