`1` . B
`2` . D
`3` . C
`4` . B
`5` . A
`II)`
`1` . The school yard is clean.
`2` . mekong river is long
`3` . grandfather is old.
`4` . Unit 20 and unit 22 are difficult
`5` . Hoan Kiem Lake is deep
`6` . Unit 1 is easy
`7` . Ha Long Bay is beautiful
`8` . Grandchildren are small
`9` . Mount Phanxipang is high
`10` . The pacific ocean is deep
`11` . Ho Chi Minh city is noisy and exciting