用所給單詞的適當(dāng)形式填空.that,foot,the,fall,都,try,they,slow,both,of.
Galileo lived in thecity of Pisa,where there is a leaning tower about 180___high.From the top ___the tower Galieo dropped a light ball and a heavy ball exactly at___same time.They___fell at about the same speed and hit the ground at the same time.He___it again and again.Every time he got the same result.At last,he decided___he had found the truth about___objects.As we know now,heavy objects and light objects fall at the same speed unless air holds___back.A feather falls more___than a stone only because the air holds the feather back more than it___the stone.
都是do