Mark Twain, one of the better known American 1.______
Writers in the nineteenth century, were born in 2._______
Missouri in the middle part of United Sates. 3._______
His hometown laid on the bank of the Mississippi 4.______
River, where he spent his young childhood. When he 5._______
grew up, he worked for a navigator on a river boat 6._______
for some time. Mark Twain was his pen name, which it 7.______
was taken from the sailor measuring on 8._______
the depth of the water. Mark Twain wrote many novels, 9._______
some of which have translated into many languages. 10.______
Keys: 1.betterbest 2.were → was 3. of →of the 4. laid →lay 5. 去掉young 6. for →as 7. 去掉it 8. 去掉on 9. √ 10.have→have been