根据短文内容和首字母提示，在下文空格处填入适当的词使短文完整。（每空一词）

Everyone knows that exercise is important. We all need to exercise. Doctors say i _小题1:____   is good for us. It makes your heart and body s__小题2:___. Children who often exercise are more alert（灵活的）. This means they do better in tests and schoolwork than those who don’t exercise.

There are many w__小题3:____ to exercise. You can walk, run, swim, skate, or play ball games. Make sure you e__小题4:___ in the following ways: you have to like what you’re doing. Exercise enough --- but not too m__小题5:____. It’s best to exercise t__小题6:___ each week. Thirty minutes each time is enough. Try all kinds of things until you find one, two or even three sports that feel r__小题7:__for you.

You can exercise at fitness centers (健身中心). They have l__小题8:____ of equipment （设备） there . The equipment will help exercise your arms, legs and other parts of your body to make you f __小题9:____. Some people buy equipment for their homes. But it is very expensive.

Exercising can be fun. Friends can exercise t _小题10:____ at a fitness center, or they can play sports together. How do you exercise?

锤击沉管灌注桩采用全长复打施工工艺时，下述（）是正确的。（）

A.第一次灌注混凝土应低于自然地面

B.前后两次沉管的轴线不应重合

C.复打施工必须在第一次灌注混凝土初凝之后进行

D.当桩身配有钢筋时，混凝土的坍落度宜采用80～100mm