[观察例句]
①To work means to earn a living.
②Learning English all by yourself is not so easy.
③It is very difficult (for us) to learn Chinese well.
④It is fun talking with a foreign teacher.
⑤They began to search the room for the thief.
⑥Your car needs repairing badly.
⑦His hobby is collecting stamps.
⑧What I would suggest is to start work at once.
