Learning a new language can increase one's knowledge and ability in their first language, because it significantly strengthen their reading, vocabulary and grammar skills.
The Answer is <u>True</u> it strengthen their first language.
Explanation: Learning another language has a lot of benefits, like better memory and better cognitive ability.
One of that benefits, is that learning another language (Especially if this new language is related to the one that you know, like English and German, or Spanish and Portuguese) you may learn some things about your own language, like shared terms, pronunciation of some "borrowed" words and things like that, so the statement is true.
