串联校正中属于相位迟后校正的是（)调节器。A．PIDB．PIC．PDD．P

.

(A) done (B) be done (C) having done (D) to have been done

Homework ________ on time will lead to better grades.

A) done

B) be done

C) having done

D) to have been done

A．Assign the homework.

B．Grade the homework and record the grades.

C．Operate the computer.

D．Learn to be a teacher.

tired and grumpy (脾气暴躁的). Not sleeping enough can also make it harder to think clearly the next day.

Sleep experts have long known that getting a good night's sleep is important.

It helps kids perform. their best during the day. A recent study shows that sleep helps improve problem-solving skills and creative(创造性) thinking.

For the study, two groups of volunteers answered a math problem. The group that slept for eight hours solved the problem correctly more often than the group that did not get enough sleep.

While you sleep, your brain is busy doing its" homework". It sorts out information from your day. Getting enough sleep each night can boost your brainpower. That will help you do your best in school. Experts say that, in return, can lead to better grades.

What is the best title for the text？

A．Too Much Sleep

B．It's Homework Time

C．Sleep to Succeed

D．Math Problems

What would Jim's girlfriend prefer him to do？

A．See her more often.

B．Spend more time in school,

C．Earn more money.

D．Get better grades.

A、Better service from regional locations

B、Transportation economies and Mixing functions

C、Risk pooling over the manufacturing or procurement lead time

D、Differentiated stocking and service policies

You had better (go) ______ over your homework before handing them in.

With the (develop) ______of economy, more people lead a better life.