1. Coming top in the exam was quite an (achieve) .

2. They have many pets, (include) three cats.

5. It took them several days to cross the Atlantic (海洋) .

4. His laziness makes it impossible for him to (实现) his dream.

2. I am sure you will (成功) .

3. They are in poor (状况) and they need help.

1. It's cold outside. You’d better put on a (厚的) coat.

5. Tom is 55 kilos. Mary is 60 kilos and I am 65 kilos. We are the heaviest students in our class.(改为同义句)

I am the heaviest in our class.

4. Russia is larger than the US. And the US is larger than China.(改为同义句) 

Russia is of .

3. I think Tom is the youngest student.(改为否定句)

2. I am 167 cm and my sister is 167 cm,too.(改为 同义句) 

I am my sister.

1. Mike is the tallest boy in my class.(改为同义句) 

Mike is than boy in my class.