Sentence:  She 'd say she did n't feel good on Sunday , could n't go to church - there 'd be a little argument , but she could be stubborn - and when the old woman had gone , quick pack the things she 'd need to take , all but the dress she 'd wear <WSD>Monday</WSD> , and take the bag down to that place in the station where you could put things in a locker overnight , for a dime . 
Meaning of the word marked with <WSD> tags:  the second day of the week; the first working day