If you want to understand Chinese language better and communicate with Chinese people more smoothly, you should expand your vocabulary and know clearly the meaning and application of similar words when youstudy Mandarin Chinese. The group of words开朗and开明are similar but easy to tell apart. The former means the space is wide and the light is sufficient as well as the thought or characters are positive like 豁然开朗 and 开朗的性格.
Generally speaking, 开明is an adjective to describe that someone is reasonable and has much common sense. It originally meant the situation from savage to civilization. In modern Chinese, it usually indicates people’s thoughts are stubborn and conservative. You can say 思想开明 and 开明人士.
开始and开头are also important words for the foreigners who are learning Mandarin Chinese should know in meanings and applications. When functioned as a verb, 开始 means to start over, usually from the very beginning or a certain point like 开始出发 and 开始比赛. If it is applied as a noun, it means the beginning time or stage. For example, 开始时，我们没有想到会遇到这么多的困难.
However, 开头can be used only as noun, meaning the first step or part or period in the process of developing things. It is often used in oral Chinese language. The most frequently seen might be 万事开头难and小说的开头. The group of words 看 and 看见 are also important and common. But 看 carries many meanings such as look , visit , observe and treat with the examples respectively 看书、看朋友、看病and看钱.
However, if you lean Chinese online free, you may learn that the meaning of look is often used. It is a durative verb and 正and正在can be added before it to indicate the action itself. However, 看见 implies the result of look , with the same meaning with see . The negative structure should be 没看见 or 看不见. The verbs indicting the processing action are not allowed after it. We can say 我一眼就看见他了.