For matching headers, the way to practice is to ‘skim read’ the paragraphs, focusing on the 1st and last sentences of each. This is usually where you can the ‘main idea’ of the paragraph.
The main idea is what the paragraph mostly talks about. There will be other things mentioned but look to see how many times they are mentioned. If only once, then the chances are that it will be a sub-topic.
Look at the sentences carefully and locate keywords which can be paraphrased or for which there are synonyms.
You do not have time to read the text ‘in-depth’ and you do not need to. You only need to understand the main idea of the text.
Rely on your own knowledge also. Think about what you know about the topic.
Practice time. – Read the sentences before you read the topic (if you feel more comfortable doing this. some people prefer to do this in reverse).
Mark the possible paraphrasing or synonyms.
Skim read the text, making notes of what each paragraph is about.
Go through the heading sentences and match the ones you think are correct.
Read the sentence and read through the corresponding paragraph to make sure it is correct.
If not, read a similar paragraph.
As you go through the text you will reduce the answers each time, giving you more chance of correctly answering the ones you are not certain of. This is a process of elimination, which is a skill you can practice.
A. i B. ii C. iii D. viii E. vii