Ants have outsmarted me on more than one occasion.In particular, there was a weekend last summer when an ant scientist was a guest at our cottage.I boasted to my naturalist friend that I could store food in an open container for a whole week and keep it safely out of the reach of house ants.Sunday night the experiment got under way.I put a large wooden tub on the kitchen floor of our cottage.After filling it to about the three-quarters mark with water, I placed a high wooden stand in the middle of it.On top of the stool, I put a saucer containing the bait: three or four pieces of rich chocolate candy.Then I painted a wide band of very slow-drying glue around the outside of the wooden tub.With that, I stood back and admired my ant trap, fully confident that the bait would be untouched upon my return to the cottage the following weekend.When my naturalist friend and I entered the cottage just six days later, ants were swarming over the bait! Here's how they put me to shame.Single files of ants had marched head-on into the band of glue around the outside of the wooden tub.A handful of them had endured martyrdom, for they had embedded themselves end to end, and made causeways of their bodies.The tempting bait on top of the stool must have caused the little creatures to use their brains to the limit.Ants hate water, but they had been courageous enough to build a highway across the stretch of water to a leg of the stool.They had assembled tiny pieces of grass and bits of wood no longer than a thirty-second of an inch, and had glued them together with saliva until their bridge extended from shore to island.Once they reached the leg of the wooden stool, traffic was almost all one way toward the chocolate bait.But there were some show-off fellows around, too; they were doing things which ants have been known to do very rarely.We noticed that a half dozen or so were walking across the ceiling, and when they came directly over the bait they let themselves fall squarely into the middle of their merry brothers.It is little wonder that I have been on the trail of ants ever since, trying to trip them up or at least learn some of the special tactics that they use.

1.The writer wanted to convince his friend that().

A.he knew more about ants than the scientist

B.he could keep ants away from food

C.ants are more intelligent than human beings

D.he could make experiments with ants

2.The experiment was carried out in().

A.the laboratory

B.an unused shed

C.the kitchen

D.the living-room

3.When the writer and his friend entered the cottage six days later, they found().

A.a lot of ants eating the chocolate candy

B.dead ants everywhere

C.swarms of ants marching around the tub

D.swarms of ants walking across the ceiling

4.The bait was().

A.in the middle of the water

B.kept on the water

C.at the top of the tub

D.on a stool in the tub

5.The ants managed to get over glue by().

A.marching courageously across it

B.going round it in single files

C.covering it with their bodies

D.making a bridge with grass and wood