減る・縮む
My work decreases.
私は仕事が減ります
My work decreases by half.
私は仕事が半分に減ります
My work decreases by half at the company.
私は会社で仕事が半分に減ります
My work decreases by half at the company from next month.
私は会社で来月から仕事が半分に減ります
My work decreases by half at the company from next month along with my colleagues.
私は同僚と一緒に会社で来月から仕事が半分に減ります