1. the / caves / Trang An / are / in / as / wonderful / the / caves / in / Ha Long / as /.

---> The caves in Ha Long are as wonderful as the caves in Trang An.

2. now / Ha Noi / the / largest / is / city / in / Viet Nam /.

---> Ha Noi is the largest city in Viet Nam now.

3. I / cheapest / think / the / in / Nha Trang / is / the / in / Viet Nam / seafood /.

---> I think the seafood in Nha Trang is the cheapest in Viet Nam.

4. the / Truong Sa / Islands / the / are / largest / islands / of / three /.

---> Truong Sa Islands are the largest of the three islands. 

5. Da Nang / city / is / the / in / Central Viet Nam / largest /.

---> Da Nang city is the largest in Central Viet Nam.

Diện tích xung quanh là : ( 4+3,5 ) x2x3 = 45 (m²)
Diện tích quét xi là : 45+ 4x3.5 = 59 (m²)
Số thời gian để quét xi là : 59x1.5 = 88.5 (phút )
                                                 Đ/S : 88.5 phút 

I + am

You / We / They + are

He / She / It + is

1.Hoa ( not read ) isn't reading book now, he ( do ) is doing his homework.

2.They ( do ) will do their homework tonight

3.Nam ( visit ) will visit Hue this summer vacation