题目内容：

Blowing bubbles is fun! The best thing about bubbles is that it's easy to make your own bubble solution(溶液). You can make as much as you want and blow as many bubbles as you'd like. Do you know the secret of making bigger and stronger bubbles? Do just as follows:

Measure 6 cups of water into one container, then pour 1 cup of dish soap into the water and slowly stir (搅拌) it until the soap is mixed in. Try not to let bubbles form while you stir.

Measure 1/4 cup of corn syrup and add it to the container. Stir the solution until it is mixed together.

You can use the solution right away, but to make even better bubbles, put the cap on the container and let your super bubble solution sit overnight. The soap mixture on the outside of a bubble is actually made of three very thin layers: soap, water, and another layer of soap. A bubble forms when the water between the layers of soap turns into gas. The corn syrup mixes with the soap to make it thicker. The thicker skin of the bubbles keeps the water from evaporating(蒸发) quickly, so they last longer. It also makes them stronger, so you can blow bigger bubbles.

Dip a bubble wand or straw into the mixture, slowly pull it out, wait a few seconds, and then blow. If you don't have a ready made "bubble wand", you can make your own bubble wand by cutting off the end of the bulb of a plastic pipet (移液管). Dip the cut end in the solution and blow through the narrow end. You can also make a circle out of thin wire or pipe cleaner. Just twist a round end on your wire to blow the bubbles through. You can even make it heart shaped, square or use other shapes if you're clever enough to bend it well.

1.The text is written to _________ .

A. argue    B. advertise    C. entertain    D. instruct

2.The secret of making bigger and stronger bubbles lies in_________ .

A. soap    B. corn syrup    C. water    D. straw

3.The bubble wand is used to_________ .

A. blow bubbles    B. mix the solution    C. measure soap    D. shape wires

4.What can we infer from Paragraph 4?

A. More soap, more bubbles.

B. Less water, better bubbles.

C. Thicker layers, more bubbles.

D. Stronger skin, bigger bubbles.