Trump, checkerboard and ride.

王牌、棋盘和策略。

A checkerboard has 64 squares.

国际象棋棋盘有64个方格。

In the field young wheat unfolds the green checkerboard.

田野里的麦苗儿铺开绿棋盘。

Methods The protocol was designed by checkerboard method.

方法采用棋盘法设计，微量肉汤稀释法测定。

Methods The protocol was designed with checkerboard method.

方法采用棋盘法设计，微量肉汤稀释法测定。