điền 1 đại từ vào chỗ trống: who/whom/whose/which/that
1 the boy _____ are playing in the garden is my cousins
2 the finally married the girl _____ he loved
3 the flowers _____ my friend gave me have withered
4 Mary is the girl ______ bicycle was stolen yesterday
5 the vegestables ______ Mr.Green sells are not fresh

Thế nào là nhiễm sắc thể?