"Mom stirs her coffee with a spoon."

Translation: 엄마께서는 숟가락으로 커피를 저으세요.

[BryantOB]

Is there any reason that coffee can't be placed in front of spoon in this sentence?

[IchbinderFremde]

No.

[RQZ.Sash]

What is the rule of the honorific conjugation? I thought if the verb ends with a consonant, you insert 으 before 시, but then isn't it 젓으세요?

[Hansol20]

ㅅ is sometimes discarded during conjugation. For example: 젓다->저으세요. 젓다->저으세요. 낫다->나으세요. But sometimes ㅅ is not discarded. For example: 씻다->씻으세요. 웃다->웃으세요. The rule for the difference is what only linguists know because the reason relates to the archaic forms of those words... There's no way but just memorize the exceptions.

[Hansol20]

"엄마께서는" should be replaced to "엄마는" or "어머니께서는". "엄마께서는"is not wrong grammartically, but sounds wierd like childish speaking in elementary school presentation.