Is text_a and text_b similar in meaning? respond with yes, related, or no.

Here are a few examples.
Example 1:
text_a: has a topic of protecting the environment
text_b: has a topic of environmental protection and sustainability
output: yes 

Example 2:
text_a: has a language of German
text_b: has a language of Deutsch
output: yes

Example 3:
text_a: has a topic of the relation between political figures
text_b: has a topic of international diplomacy
output: related

Example 4:
text_a: has a topic of the sports
text_b: has a topic of sports team recruiting new members
output: related

Example 5:
text_a: has a named language of Korean
text_b: uses archaic and poetic diction
output: no

Example 6:
text_a: has a named language of Korean
text_b: has a named language of Japanese
output: no

Target:
text_a: {text_a}
text_b: {text_b}
output: