可能补语（1）

Potential complement (1)

“得/不” is inserted between a verb and a resultative or directional complement to indicate whether or not a certain result can be attained or a certain status can be achieved.

V + 得/不 + Resultative/ Directional Complement
看 得              懂            （can understand after reading）
做     不          完 (can finish doing)
上 得                            去 (can get up)
爬     不                       上去 （cannot climb up）

The V/A-not-V/A question for a sentence with a potential complement is “
V + 得/不 + complement +V + 不 + complement”. When the verb is followed with an object, the object is placed after the potential complement. For example,
A: 你看得见看不见那个小木屋？
B: 小木屋在哪儿？我看不见。
A: 下午五点钟你回得来回不来？
B： 我回得来。

Notes（1）The negative form of the potential complement is used more frequently than the positive form. It indicates that due to a lack of certain subjective or objective condition(s), the action will not be able to achieve a certain result or reach a certain status. This notion usually can only be expressed by using the potential complements and not with optative verbs. For example,
我只学了一年汉语，现在看不懂《红楼梦》。
（One can not say : “我只学了一年汉语，现在不能看懂《红楼梦》。”）
老师说得太快，我听不懂。
(One cannot say：“老师说得太快，我不能听懂。”)
山很高，我爬不上去。
（One cannot say ：“山很高，我不能爬上去。”）
我向来很长时间，想不出好办法来。
（One cannot say ：“他想了很长时间，不能想出好办法来。”

（2） The positive form of the potential complement is rarely used. It is only used to ask or answer a question with a potential complement. For example,
A: 你做在后边，听得清楚吗？
B:我听得清楚。