(Original Publication Date, 30 May 1991)
Panel 1: A few minutes later, we find John holding the basket and asking Elly that given all of the baby clothes and diapers, wouldn't it be a good idea if they used the clothesline in order to lower their monthly power bill. Elly guesses so.
Panel 2: This leads to him staring awkwardly at her as she holds April because he doesn't realize what she means by "I guess so."
This is because he probably means "wouldn't it save money if YOU put stuff on the clothesline" or something like that.
Panel 3: They remain in the same pose in order for it to look like she's about to say one of three things: "If you want to do that, do it yourself" or "But would it save time?" or "Is the 'easy' thing watching ME do all that?"
Panel 4: Since he correctly guesses that Elly means all three things by "I guess so", we find him stuffing clothes into the dryer.
Summary: What John never realizes is that the kids and dog see laundry on a clothesline as something that's in the way of their fun. This is another thing Elly really means by "I guess so."