I often go to school by bike because it's good for my health.（我经常骑自行车去上学，因为这对我的健康有好处。）

She likes reading books in her free time and has read many interesting stories.（她喜欢在空闲时间读书，并且已经读了很多有趣的故事。）

They will play football this afternoon if the weather is fine.（如果天气好的话，他们今天下午将踢足球。）

My mother is cooking dinner in the kitchen while I am doing my homework.（我妈妈正在厨房做晚饭，而我正在做作业。）

He has been to Beijing twice and wants to go there again.（他去过北京两次，还想再去那里。）

We should protect the environment by reducing waste and saving energy.（我们应该通过减少浪费和节约能源来保护环境。）

The movie was so exciting that everyone in the theater was attracted.（这部电影非常刺激，以至于电影院里的每个人都被吸引了。）

You need to practice speaking English every day to improve your oral English.（你需要每天练习说英语来提高你的英语口语。）

It took me two hours to finish this difficult math problem.（我花了两个小时才完成这道难题。）

They are planning a picnic in the park for the weekend.（他们正在计划周末去公园野餐。）

My father used to smoke a lot, but now he has given it up.（我父亲过去抽烟很多，但现在他已经戒掉了。）

The new library in our school is very big and has a lot of books.（我们学校的新图书馆非常大，有很多书。）

She was late for school this morning because of the heavy traffic.（由于交通拥堵，她今天早上上学迟到了。）

We had a great time at the party last night, singing and dancing.（昨晚我们在聚会上玩得很开心，又唱又跳。）

He is too young to understand this complicated problem.（他太小了，无法理解这个复杂的问题。）

If you want to pass the exam, you must study hard from now on.（如果你想通过考试，你必须从现在开始努力学习。）

The beautiful flowers in the garden make the whole place look wonderful.（花园里美丽的花朵让整个地方看起来很棒。）

They were talking about their dreams when the teacher came into the classroom.（当老师走进教室时，他们正在谈论他们的梦想。）

I have lost my key. I don't know where I put it.（我丢了我的钥匙。

我不知道我把它放在哪里了。）

We should be kind to others and help those in need.（我们应该善待他人，帮助那些有需要的人。）