正的用法和样例：
例句
-
他的帽子没戴正。
His hat isn't on straight. -
他对著镜子看领带是否系正。
He looked in the glass to check that his tie was straight. -
他似乎把正号误作负号了。
He seems to have mistaken a plus for a minus. -
正数的数目是无穷的。
The number of positive numbers is infinite. -
这个电荷是正电荷。
This charge is a positive charge. -
请等等！我帮你正正领带。
Just a minute! Let me put your tie straight. -
我们是朝正北方向航行。
Our course was straight to the north. -
我的领带系得正不正？
Is my tie straight?
