The Chinese word '讲座' is used in a context similar to the English word 'lecture'. It often refers to a talk or speech given to a group, especially students. However, '讲座' can also refer to a series of talks on a particular subject.

In Chinese, '启用' is a verb which denotes an action to make something operational or active. It is usually used in contexts where you describe the start of something, primarily in technological or systematical settings.

The Chinese word '以上' is used to indicate something which is 'above' or 'more than'. It is less commonly used to refer to physical location than the English 'above', and is often used in formal or mathematical contexts.

The Chinese word '搜索' is widely used in various contexts, similar to the English word 'search'. It can be used to explain the act of finding information in files, databases, or other digital sources, or searching for a person or thing in the real world. It is common in both conversational and written Chinese, making it a useful word for students to learn.

The word '频繁' in Chinese is often used to express something that happens or appears often or a lot of times. Like the English word 'frequent', it can be used in various contexts including frequency of events, actions, or occurrences.

The Chinese word '某处' has the same usage as 'somewhere' in English. It is often used to denote an indefinite or unspecified location. The word combines '某' meaning 'some' or 'a certain' and '处' meaning 'place' or 'location'.