Your feet must be behind the line when you serve.
發球時你的腳必須站在底線的外面。
She shifted her weight from one foot to the other.
她把身體的重量從一只腳換到另一只腳上。
It was the first time I had set foot on American soil.
那是我第一次踏足美洲大地。
You can back up another two feet or so.
你可以再退兩英尺左右。
It was the first time I had set foot on African soil.
那是我第一次踏上非洲大地。