My brother was earning much less in his previous job than he is now

=> My brother is earning much more in his current job than he was in the past.

Have you got any bigger shirt than that one

=> Is that the biggest shirt you have got?

I am not taller than anyone in the class

=> I am the lowest in the class

The company's revenue in May is the highest compared to the previous months (tại sao 's lại viết thành is @@)

=> The company's revenue in the previous months is lower than that in May.

Sting is the most dedicated singer in the music business

=> There isn't a more dedicated singer in the music business than Sting. 

Đáp án:

1. My brother is earning much more in his present job than his previous job.

2. Is this the biggest shirt you have?

3. I am the lowest student in the class.

4. The company's revenue in the previous months is lower than the revenue in May.

5. There isn't any singer more dedicated than Sting in the music business.

     Chúc bạn học tốt ^ω^

            -Minhh-