One character a day, easy to master Chinese characters. Let's take a look at the basic knowledge of "开".

开 kāi  
Explanation：Open
Phrases：开车(kāi chē) drive or start a car ； 开花(kāi huā) blossom;bloom
最早的“开”字由三部分组成：两边两扇门，门中间的一横代表门闩，门闩下边是一双手，表示用手去移动门闩。“开”的愿意就是“开门”，后来逐渐演变出其他的意思。
The original character开was comprised of three parts: on the two sides were the double doors ; in the middle of the doors there was a horizontal stroke representing the bolt ; and under the boltthere was a pair of hands, indicating two hands removing the door bolt. The original meaning of 开 is “to open the door”, but later it came to mean “to open” in a general sense.           

Sentences:

1. Kāichē yídìng yào zhùyì jiāotōng biāozhì.
    开车一定要注意交通标识。
    One must pay attention to the traffic signs.

2.Zhè xiàng xīnjìshù zài nóngcūn yǐ biàndìkāihuā.
    这项新技术在农村已遍地开花。
    The new technology has already taken off in the countryside.