On video, Doctor Zhong Nanshan ________ teenagers to study hard in the first lesson of this term.( )
A.allowedB.trainedC.encouraged
Here are many_______ and________.
This blue pen is .
Look! Some ______ are in the school.
--Are those the ______ books? -- No, they are ______ books.
--______ are they? --They are my ______.