After learning some basic Chinese words, the foreign students need to master some grammar points to connect the words together to express the complete meanings. One of frequently used grammar points that the students who study in Mandarin language courses in China need to know is verb + 过 which is applied to indicate a past experience. If you want to express that you have ever been to China, you can say我以前去过中国.

When a verb is immediately followed by the dynamic auxiliary 过, it indicates that the act was taken place in the past and is the act has stopped when speaking of it. It is to emphasize the past experience. The affirmative form of it is verb + 过. For example, 来中国以后，我去过北京、上海和昆明, which is to say, the speaker is no longer stay in Beijing, Shanghai and Kunming.

On the contrary, if you intend to express that you have never gone somewhere of never done something, you need to follow the pattern 没（有）+ verb + 过 such as 我没吃过北京烤鸭. Another patter in the affirmative-negative question form verb + 过+ object +没有？ to ask whether certain act happened or not. For instance, 你去过香港没有？

Another language point that the foreign students need to learn when they go to school to study in China is the complement of frequency which is to indicate the frequency of an act. You need to pay attention to that the complement of frequency is used to indicate the number of times of an act has occurred. This type of complement is formed by a numeral and a verbal classifier such as 次、声、躺、下, etc. The aspect particles of 了and过are placed after the verb and before the complement. For examples, 他来过两次中国and他敲了一下儿门.

If the object is a noun referring to things, it must be placed after the complement of frequency. If the object is a personal pronoun, it is usually put before the complement. However, if the object is the name of a person or place, it can be placed before or after the complement.