It is not too difficult to fill in the blanks. Just 12 16. It's not easy to remember, but it's not difficult.

The big question 19 is not often tested, but it is not difficult.

It can be said that only the derivative is difficult in the big questions, and the other questions are moderately difficult.

The national college entrance examination questions are simpler and more difficult year by year. 20 14 is relatively simple, while 20 15 will be relatively difficult.