23. Peter could skate when he was 12. 

could + V1 : có thể làm gì 

24. They haven't visited Europe for two years.

S + has/have +  not + V3/ed + for/since +time

= The last time + S+ V2 /ed + was + time 

25. Humans are more intelligent than robots.

S + be+ more + long-adj + than + O : ss hơn 

26. Overpopulation brings many problems like crimes and unemployment

S số ít + Vs/es: thì hTĐ

N and N: và 

27. Every country should do something to control population.

should + V1: nên làm gì

to + V1: để làm gì 

28. Some measures should be taken to empower laws

Some + N số nhiều / N ko đếm được 

S+ should be + V3/ed: bị động - modal verb 

to + V1: để làm gì 

29. People must be aware of the effects of overpopulation.

must + V1: phải làm gì 

be aware of + sth / N : nhận thức về 

the + N of N 

30. Methods to control the population should be carried out soon.

S + should be + V3/ed: bị động - modal verb 

`color{orange}{~MiaMB~}`