1. Everyone learns his own language by remembering (dòng thứ 2) ....... as easily as one (dòng 4).
2. Because pupils have too little time for it, and they are busy with other subjects as well
3. Dòng thứ 4 từ đầu đến ... in our mind (dòng 3)
4. No, it isn't
5. We should learn new words in sentences