9. Keeping pets can waste a lot of energy.
养宠物要花费很多精力。
还能这样说：
You need to spend a lot of energy to keep pets.
A lot of energy is needed to keep pets.
谚语：
Waste not, want not.
俭以防匮。
10. You should look after your pets and not disturb others.
你应该看管好自己的宠物，不要影响到其他人。
还能这样说：
Your pets should be carefully watched and are not allowed to disturb others.
In order to avoid disturbing others, you should attend to your pets.
应用解析：
disturb the peace 扰乱治安
11. I hate pets in my community.
我讨厌我们小区的宠物。
还能这样说：
Pets in the community are my nuisance.
I don't like pets in my community.
谚语：
A pet lamb makes a cross ram.
宠坏的小羊将成为脾气坏的大羊。
12. My dog is ailing.
我的狗生病了。
还能这样说：
My dog has fallen ill.
My dog is sick.
应用解析：
a gay dog 一个快乐的人；
dog sb.'s steps 跟踪某人；
sick as a dog 病得厉害