A new language can sound strange the first time you hear it, but you learn to listen to it before you speak. ( ) shouldn’t
( ) must
( ) mustn’t
( ) may
( ) should

Should

Explanation:

You should learn to listen to it before you speak.

Hope this helps!

should

Explanation:

Shouldn't and musn't is not appropiate to the statement

Must makes it seem like you HAVE to do it, like in a forceful tone

Should implies that you should consider listening to it in a more softer tone

16.) true

17.) true

18.) it doesn't say

19.) true

20.) false

explanation: