Question

if you have learned it well , you ______ do these exercises

if you have learned it well, you ____ do these exercises.
A. don't need B. needn't to C. don't have D. don't have to
怎么做啊啊.. 解释一下.. 谢谢各位..

Answer 1

选D
首先NEED可以做实义动词，有动词词组need to do ,其否定形式为don't neeed to do译为：需要做什么；
need 也可作助动词（诸如will,can....)，所以又可加动词原形，即need do,也是“需要做什么”的意思
第一项：need作实义动词，所以该改为don't need to,
第二项：need 作助动词，故应改为needn't
第三，四项区别have do（叫某人做什么）和have to do（不得不做什么）的意思

若选D，则该句意为：如果你已经把它学好了，那么你就没有必要再做这些练习了。

希望能帮到你，加油咯！

Answer 2

D. don't have to
此句的意思是如果你已经学的不错，就不必做练习了

A错在don't need to do，to没有
B. needn't to 错在 . needn't do, . needn't 是情态动词
C. don't have to do和A一样的道理

祝你进步，有不会的可以再问我哦
我很乐意为您解答疑惑O(∩_∩)O~

Answer 3

D needn't do sth 或 don't need to do sth
这里只有don't have to 符合题意。

Answer 4

D

Answer 5

D