there were many people waiting_______.a.at the doctor b.in the doctor c.at the doctor's

问题描述:

there were many people waiting_______.a.at the doctor b.in the doctor c.at the doctor's

C. at the doctor's 这里只是省略了一个字,office (或者 clinic)
因为大家都很清楚 doctor 是干啥的,所以不管办公室也好,诊所也好说了都是多余。在实际生活用语中经常会被省略。
如此,这句话选 C 就显而易见了。 at the doctor's office (clinic).

选C
at the doctor's 在医院
类似的如at the barber's 在理发店

at the doctor's
意思是:在医生那里/在医院
固定搭配.