8.
1-Charles has a good knowledge of the subject
2. These children are badly behaved! They need more direction
3. Everyone agrees that a good example is important
4. If you don't know a word, look it up in your dictionary
5. Maths is easy if you are allowed to use a calculator
6. Sam spent four years studying at university
7. Some apes seem to have as much intelligence as humans!
8. I find listening to comprehension tests rather difficult
9. At the age of eleven i went to secondary school
10. I enjoyed doing experiments in the laboratory
good night you