Hold the floss tightly between your thumbs and forefingers, with about an inch (2.5 cm) of floss between them.

两只手的食指和大拇指分别捏紧牙线的一端， 中间留出一英寸长（2.5厘米） 。

The old man tapped the steering wheel once with his foreFingers.

那位老爷子用食指轻轻拍着方向盘。

Use the thumbs and forefingers to guide the floss between the teeth.

握紧牙线，用食指和拇指轻柔地在牙缝间操作牙线。

The ornithologists made Vs with their thumbs and forefingers, measuring angles.

鸟类学家们用大拇指和食指构成V形量测角度。

If you use your thumbnails to click your mouse buttons instead of your forefingers, you get a much better result.

要是你用拇指来代替食指敲击鼠标键的话，效果会更好的。

Use your thumbs and forefingers to gently pull the floss from the gumline to the top of the tooth to scrape off plaque.

用拇指和食指沿着齿龈向牙冠方向缓和地拉扯牙线，以去除牙菌斑。

As the story goes, over years ago, the French disabled the English archers they captured in battle by cutting off their middle and forefingers.

就像一个故事那样，在很多年前，法国人在战场上切断他们的俘虏中英国弓箭手食指。

Above your head the best way to catch a ball above your head is by joining the thumbs and forefingers of your hands together so there is a small arch between your hands.

过顶球处理过顶球的最佳方法是用大拇指和其他手指一起来接球，因为那样双手之间可形成一个拱形。