Teacher: In this task, you need to write a topic word from the given fact. The topic word must have at least one word overlap with the given fact. The topic word often involves adding a new word from a related concept. In your topic word, use at least one word from the given fact. Topic words with two or more words work best.
Teacher: Now, understand the problem? If you are still confused, see the following example:
Fact: pesticides cause pollution.
Solution: pollution harms.
Reason: This is a good topic word, because it contains one overlapping word "pollution".

Now, solve this instance: Fact: Roots grow in length and width from primary and secondary meristem.
Student:
meristem plants.