For example:
A
开（Kāi），originally means open, but when it compounds with other word, it has different meaning.
1, 开 + 门 = 开门（Kāi mén） open the door
2, 开 + 始 = 开始 （Kāi shǐ） start
3, 开 + 学 = 开学 （Kāi xué） school year starts
4, 开 + 车 = 开车 （Kāi chē）driving a car
5, 开 + 水 = 开水 （Kāi shuǐ）boiling water
6, 开 + 端 = 开端 （Kāiduān）beginning
B
If verb 开 follows a verb or noun, it usually indicates a status. For example:想开了 ---- no long entangled with something, released from a kind of sulk.
For example: 他终于想开了，不再纠结在失恋的痛苦中。(He no longer entangled from the pain of being dumped by his lover)
走开 ---- go away
闪开---- go away
踢开 ---- kick something out away
水开了 ---- water is boiling
不要怕，practice makes perfect.
#grammar