1. The upper middle case has nine lowercase letters, with four lines and three squares: B, D, F, H, I, K, L, T and U. Note that when writing with the upper middle case, the top of the stroke must be close to the first line.

2. Four rows and three squares have 12 lowercase letters: ι, o, e, u, z? C, S, N, M, R, W, X, they are in the middle grid. The upper end of the stroke should be close to the second line and the lower end should be close to the third line.

There are four lowercase letters in three squares of four lines: p, q, y, π. These letters are written in the middle and lower squares, and the lower end of the strokes should be close to the fourth line.

4. There are only 1 small letters in the upper, middle and lower cells in the four lines and three cells, and the word J should not stand on the top of the world in the four lines and three cells.

Extended data:

In addition to occupying the case, we should also remember the specific requirements of phonetic writing: in the four-line case, the upper case is not the top case, the middle case is full, and the lower case is not along the bottom (see the children's song collection "Phonetic Writing Songs" for details); Vertical painting should be straight, curved painting should be round, and letter writing should be full.

Learning Chinese Pinyin requires not only reading and writing, but also knowing the position of letters in four lines and three cells, that is, which cell each letter should be written in and how many cells it needs to occupy, so as to standardize the writing of letters.