1. A body of water, smaller than a river, contained within relatively narrow banks?
2. What the thing you push around the grocery store/supermarket?
A shopping trolley.
3. A metal container to carry a meal in?
4. The thing that you cook bacon and eggs in?
5. The piece of furniture that seats three people?
6. The device on the outside of the house that carries rain off the roof?
Gutters and drainpipe.
7. The covered area outside a house where people sit in the evening?
Conservatory. Or if they're posh they may have a gazebo.
8. Carbonated, sweetened, non-alcoholic beverages?
Soft drink or pop.
9. A flat, round breakfast food served with syrup?
I'm guessing this means a pancake...
10. A long sandwich designed to be a whole meal in itself?
11. The piece of clothing worn by men at the beach?
12. Shoes worn for sports?
Trainers or plimsoles.
13. Putting a room in order?
14. A flying insect that glows in the dark?
Firefly. Never seen one, though...
15. The little insect arthropod that curls up into a ball?
Slater or woodlouse
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?
17. How do you eat your pizza?
With cutlery. Or with fingers. It doesn't really matter.
18. What's it called when private citizens put up signs and sell their used stuff?
Car boot sale.
19. What's the evening meal?
Dinner or tea. Depends on whether it's cooked or cold.
20. The thing under a house where the furnace and perhaps a rec room are?
Basement or cellar. But what's a rec room?
21. That plant that kids throw at each other because it sticks to clothing?
Goose grass or cleavers. Then there are the teazles on the dunes...
22. Those little balls of froth on plants in spring, which contain some moth or other's eggs?
Cuckoo spit. And it's a frog hoppper not a moth. Unless of course you're thinking of the stuff produced by Burnett moth larvae, but they're now so rare that you hardly even see them on Les Mielles...
23. Girls' lower-half underwear?
Knickers or panties.
24. Boys' lower-half underwear?
24. The cloth you had when you were little and always slept with, and perhaps sucked your tongue with?
I had a bear called Bluie and another called woofer
25. Warm knitted top typically made of wool?
26. Baked in an oven, made of flour, butter, an egg, milk: raised with a chemical baking powder (cream of tartar/bicarbonate of soda) rather than with a yeasty leaven: what do you call it?
27. A single thistledown seed flying free?