From the official site:
Find out if you have the language proof for citizenship: Step 1
If you’re 18 to 54 years of age, you must submit proof that you can speak and listen at the Canadian Language Benchmarks (CLB) Level 4 or higher in English or French.
To do this, you must send at least one of the documents we accept as proof with your citizenship application.
We will review the language proof you send us. We won’t process your application and will return the entire application to you if your proof:
- can’t be read
- isn’t included with the application
- is in a language other than English or French (without a certified translation)
Answer these questions to find out if you have proof we’ll accept.
Did you or do you attend a secondary or post-secondary program in English or French?
The program can be in or outside Canada.
If you did, send a copy of proof that you completed or are attending a program with your application. Proof can be your:
- diploma
- transcript
- certificate
Your proof must be in English or French. If it’s in another language, you must also send a
certified English or French translation. The translation should show that the language of instruction of the program was English or French