Explanation:

1. People's knowledge and experience gained in practice

2. People you know; friend

3. Refers to the cultural and academic.

4. know; understand

Make sentences:

(1) Youth Daily is my first reading, which has made me understand a lot of knowledge and truth.

(2) People who don't read books and newspapers are bound to have narrow knowledge.

(3) This craft does not need profound theoretical knowledge.

(4) Learning should be constant to gain more knowledge.

(5) In class, we usually review what we have learned first, and then talk about new lessons.

(6) We should have the spirit of dropping water and penetrating stones when learning knowledge.

(7) In learning, we should enrich our knowledge with the attitude of collecting arms and making a mickle.

(8) Learning is the only doorway to the temple of knowledge.

He is working hard in the field of knowledge.

(10) Welcome intellectuals to settle down in the countryside.