`41` That ruler is shorter than this ruler 

`-` short >< long : ngắn >< dài

`-` S + be + short-adj thêm er + than + N/pronoun 

`42` Is this the most expensive computer do you have ? 

`-` S + be + more + long-adj + than + N/pronoun 

`-` S + be + the most + long-adj + (N) + ... 

`43` Why don't we play chess this afternoon ? 

`-` Why don't we + V-inf ? 

`-` What/How about + V-ing ? 

`44` She would rather read books than watch TV 

`-` prefer + N/V-ing + to + N/V-ing 

`-` would rather + N/V-inf + than + N/V-inf

`45` What is his weight ? 

`-` heavy (adj) : nặng `->` weight (n) : cân nặng 

`-` How + adj + be + S ?

`-` What + be + (TT sở hữu) +  S ? 

`41`.That ruler is shorter than this one

`\rightarrow` So sánh hơn : S1 + be + adj-er / more adj + than + S2

`42`.Is this the most expensive computer you have ?

`\rightarrow` So sánh nhất : S + be + the adj-est / the most adj

`43`.Why don't we play chess this afternoon ?

`\rightarrow` Why don't we + V ?

`44`.She would rather read books than watch TV

`\rightarrow` S + would rather + V + than + V : Muốn làm gì hơn là làm gì

`45`.What is his weight ?

`\rightarrow` Thì HTĐ ( CNV - ĐT Tobe ) : Be + S + adj / n ?

`\text{@ TheFox}`