In this seminar, I will talk about two new results. (1) Proof of Catanese-Chen-Zhang conjecture: $K_X^3/geq 4/3p_g(X)-10/3$ holds for all projective Gorenstein minimal 3-folds, which is a joint work with Jungkai Chen; (2) Answer to the following open problem: for any integers n>2, 0<l<n, m>0, there exists a n-dimensional nonsingular projective variety X of general type so that X is canonically fibred by l-dimensional sub-varieties with the fiber volume >m. This disproves the so-called "desired canonical boundedness". This is a joint work with Zhi Jiang.