S

---Excuse me, how much is the jacket? ---It’s 499 Yuan. ________.

---It’s rather cold in here. Do you mind if I close the window? ---____________.

His driver’s license was _________ because he was caught drunk-driving

Don't try __________ across the river. It’s dangerous

Mr. John promised to look ________ Sandra’s paper, that is, to read it carefully before the defense

串联管路中，S表示调节阀（ ）。

串连管路中，随S值下降，等百分比特性畸变，趋近于直线特性。( )

串联管路中，随S值下降，等百分比特性畸变趋近于直线特性。( )

在MCS-51系统中，若晶振频率是6MHz，一个机器周期等于(    ) μs。

等直杆件AB的转动刚度S_AB（　）。