WHAT DO YOU CALL ...
1. a body of water, smaller than a river, contained within relatively narrow banks?
That's also a river. I just never saw a real river growing up. They're big, right?

2. the thing you push around the grocery store?
My little brother, Ian.

3. a metal container to carry a meal in?
Pringles

4. the thing that you cook bacon and eggs in?
the microwave?

5. the piece of furniture that seats three people?
that would be the FLOOR

6. the device on the outside of the house that carries rain off the roof?
the giant fiberglass fish

7. the covered area outside a house where people sit in the evening?
the bus stop

8. carbonated, sweetened, non-alcoholic beverages?
Yes! I mean Soda. I had a friend from the midwest who said "pop" all the time, I thought he had seen it in a Roald Dahl book.

9. a flat, round breakfast food served with syrup?
Waffle.

10. a long sandwich designed to be a whole meal in itself?
"a sandwich". gad here's another example of something I didn't see until I already had my basic vocab. When I finally did learn about these, I learned a bunch of words at once. Grinder, po' boy, hero, dagwood, submarine sandwich, hoagie. They all sound disgusting, except "hero", which sounds greek.

11. the piece of clothing worn by men at the beach?
Well, this is Seattle, so "fleece". If we're talking about the majority of my life, "Jams" or "Baggeez".

12. shoes worn for sports?
feet spaceships

13. putting a room in order?
roomsort

14. a flying insect that glows in the dark?
mosquito which has been sprayed with aqua net and ignited

15. the little insect that curls up into a ball?
'Mr. Potato Bug'

16. the children's playground equipment where one kid sits on one side and goes up while the other sits on the other side and goes down?
teeter-totter/see-saw/i-am-so-alone-and-stationary

17. how do you eat your pizza?
(flamboyantly rotating the slice to point the crust at the camera) I eat it BACKWARDS!

18. the act of private citizens putting up signs and selling their used stuff?
ebay? garage sale/yard sale/rummage sale? And we call it "pre-owned", not used. Better positioning.

19. the evening meal?
breakfast/none

20. the thing under a house where the furnace and perhaps a rec room are?
ZION

Supplementary 1. a store which primarily sells alcohol?
Alcohol 'n Things

Supplementary 2. the place where a hose is attached to its water source?
The hose-water interface

Extra 1: Where I grew up, most folks speak pidgin which means that the answers to most of these would really be "da kine."