这幅画的焦点是中间的那朵红花。

The ___focal point of this painting is the red flower in the center.

这个显微镜的焦距可以调节以获得更清晰的图像。

The microscope's ___focal distance can be adjusted for sharper images.

这次会议的主要议题是气候变化。

Climate change is the ___focal topic of this meeting.