わけがない

Phrase (Intermediate ㊥ 578)

A phrase which negates the existence of a reason to believe that someone does something or is in some state, or that something takes place; or which negates a possibility of someone's doing something or being in some state, or something's taking place.

Equivalent: There is no reason why ~; it is impossible (for ~) to ~; cannot

こんな易しい仕事が君に出来ないわけがない。
There is no reason why you cannot do such an easy job.
日本語がそんなに速くマスター出来るわけがない。
It is impossible to be able to master Japanese that quickly.
そんなことをしていいわけがない。
No one is allowed to do that kind of thing. (literally: There is no reason why it is all right to do such a thing.)
そんなことを言って人が喜ぶわけがない。
There is no reason for people to be pleased if you say such a thing to them.
彼女がそんなひどいことを言うわけがない。
There is no reason for her to say such a terrible thing. / It is impossible for her to say such a terrible thing.
彼はあんなに酔っていて大丈夫なわけがない。
Being that drunk, he cannot be all right.
あの店の物がこんなに安いわけがない。
Things at that shop cannot be this cheap.
彼女がこの時間にこんな所にいるわけがない。
It is impossible for her to be in such a place at this time (of the day).
彼がこの学校の卒業生であるわけがない。
It is impossible for him to be a graduate of this school.

Formation

(i) {V/Adjective い}informal nonpastわけがない
分かるわけがないIt is impossible to understand
面白いわけがないIt is impossible for something to be interesting
(ii) {Adjective な} stemなわけがない
奇麗なわけがないIt is impossible to something to be clean
(iii) Nounであるわけがない
先生であるわけがないIt is impossible for someone to be a teacher

Notes